Obesity and insulin resistance in resistant hypertension: implications for the kidney

Prevalence of kidney disease in patients with different types of cancer or hematological malignancies: a cross-sectional study

PURPOSE

This study investigated the prevalence and risk factors of acute kidney injury (AKI) and chronic kidney disease (CKD) in cancer patients with the aim of providing guidance for clinical treatment of cancer patients.

METHODS

A retrospective study was conducted on all cancer and hematological malignancy patients admitted to Xuanwu Hospital, Capital Medical University, from January 2018 to July 2023. The study population included patients aged 18-80 years with a confirmed cancer or malignancy diagnosis. Chi-square tests, Spearman's correlation, and logistic regression were used to evaluate the relationships between demographic factors, comorbidities, cancer types, antitumor drugs and the prevalence of AKI/CKD.

RESULTS

Among the 2438 participants, the prevalence rates of AKI and CKD were 3.69% and 7.88%, respectively. Patients with diabetes had higher prevalence of AKI/CKD than those without diabetes (OR = 1.66, 95% CI 1.01-2.68, p = 0.040; OR = 1.60, 95% CI 1.10-2.31, p = 0.012, respectively). In addition, a higher prevalence of CKD was observed in patients with hypertension (OR = 3.49, 95% CI 2.43-5.06, p < 0.001). Underweight patients were more likely to develop AKI (OR = 2.66, 95% CI 1.03-6.08, p = 0.029). Anthracyclines may contribute to a higher risk of AKI, and antimetabolites and immunomodulators may be associated with the development of CKD. Overall, patients with hematological malignancies had significantly higher rates of AKI/CKD than those with solid tumors. Among solid tumor patients, the prevalence of AKI/CKD was low in patients with lung and breast cancer.

CONCLUSIONS

AKI and CKD prevalence varies across cancer types, influenced by factors, such as diabetes, hypertension, body weight, and antitumor drugs. Tailored treatment plans are essential for improving cancer patient outcomes.

Changes in the triglyceride-glucose-body mass index estimate the risk of hypertension among the middle-aged and older population: a prospective nationwide cohort study in China in the framework of predictive, preventive, and personalized medicine

Background

Hypertension is a major modifiable cause of cardiovascular diseases and premature death worldwide. The triglyceride-glucose-body mass index (TyG-BMI), as a novel indicator, has been proposed for assessing hypertension risk. Nevertheless, a paucity of studies has explored the predictive potential of dynamic TyG-BMI for hypertension. The purpose of this study was to investigate whether cumulative TyG-BMI could better predict hypertension incidence and explore the interplay between TyG and BMI in hypertension development. From the perspective of predictive, preventive, and personalized medicine (PPPM/3PM), we assumed that dynamic monitoring of TyG-BMI level and joint assessment of TyG and BMI provide novel insights for individual risk assessment, targeted prevention, and personalized intervention of cardiovascular diseases.

Methods

Using data from the China Health and Retirement Longitudinal Study (CHARLS), a nationwide cohort conducted between 2011 and 2018, the changes in TyG-BMI between 2012 and 2015 were categorized into four groups by K-means clustering analysis. Cumulative TyG-BMI was also divided into four levels based on quartile cutoffs. Logistic regression and restricted cubic spline analyses were performed to examine the associations of different TyG-BMI classes with hypertension. Mediating and interactive analyses were utilized to discern the mutual effects between TyG and BMI in hypertension development.

Results

A total of 2891 participants were enrolled, among whom 386 (13.4%) developed hypertension during a median 36.5-month follow-up period. Logistic regression analysis revealed that, compared to participants with persistently low TyG‑BMI, an increased risk of hypertension was observed among those with a moderate (odds ratio (OR) = 1.60, 95% confidence interval (CI) 1.15 to 2.22), a higher (OR = 1.93, 95% CI 1.28 to 2.89), and the highest TyG‑BMI (OR = 2.33, 95% CI 1.35 to 4.03). A positive linear association of cumulative TyG-BMI with hypertension was discovered (P for non-linear = 0.343). Furthermore, TyG partially mediated the relationship between BMI and hypertension, accounting for 13.18% of the total effect. The joint effect of BMI and TyG was positively affiliated to hypertension development.

Conclusions

This study demonstrated a significant positive association between dynamic TyG-BMI and hypertension among the Chinese middle-aged and older population. In the context of PPPM/3PM, long-term monitoring of TyG-BMI could assist in identifying individuals at high risk of hypertension, strengthening primary prevention efforts and facilitating prompt intervention strategies. In addition, this study revealed the mutual effect of TyG and BMI on hypertension development, which provides a novel approach for mitigating the risk of cardiovascular diseases via addressing metabolic disorders, thereby enhancing effective prevention and targeted intervention.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00380-6.

Nutritional assessment and medical dietary therapy for management of obesity in patients with non-dialysis chronic kidney disease: a practical guide for endocrinologist, nutritionists and nephrologists. A consensus statement from the Italian society of endocrinology (SIE), working group of the club nutrition-hormones and metabolism; the Italian society of nutraceuticals (SINut), club ketodiets and nutraceuticals "KetoNut-SINut"; and the Italian society of nephrology (SIN)

PURPOSE

Chronic kidney disease (CKD) is a serious health concern with an estimated prevalence of about 13.4% worldwide. It is cause and consequence of various comorbidities, including cardiovascular diseases. In parallel, common pathological conditions closely related to ageing and unhealthy dietary habits increase the risk of CKD development and progression, including type 2 diabetes and obesity. Among these, obesity is either independent risk factor for new onset kidney disease or accelerates the rate of decline of kidney function by multiple mechanisms. Therefore, the role of diets aimed at attaining weight loss in patients with obesity is clearly essential to prevent CKD as to slow disease progression. Various dietary approaches have been licensed for the medical dietary therapy in CKD, including low-protein diet and Mediterranean diet. Interestingly, emerging evidence also support the use of low-carbohydrate/ketogenic diet (LCD/KD) in these patients. More specifically, LCD/KDs may efficiently promote weight loss, improve metabolic parameters, and reduce inflammation and oxidative stress, resulting in a dietary strategy that act globally in managing collateral conditions that are directly and indirectly related to the kidney function.

CONCLUSION

This consensus statement from the Italian Society of Endocrinology (SIE), working group of the Club Nutrition - Hormones and Metabolism; the Italian Society of Nutraceuticals (SINut), Club Ketodiets and Nutraceuticals "KetoNut-SINut"; and the Italian Society of Nephrology (SIN) is intended to be a guide for Endocrinologist, Nutritionists and Nephrologist who deal with the management of patients with obesity with non-dialysis CKD providing a practical guidance on assessing nutritional status and prescribing the optimal diet in order to best manage obesity to prevent CKD and its progression to dialysis.

Exploring potential targets for natural product therapy of DN: the role of SUMOylation

Diabetic nephropathy (DN) is a common and serious micro-vascular complication of diabetes and a leading cause of end-stage renal disease globally. This disease primarily affects middle-aged and elderly individuals, especially those with a diabetes history of over 10 years and poor long-term blood glucose control. Small ubiquitin-related modifiers (SUMOs) are a group of reversible post-translational modifications of proteins that are widely expressed in eukaryotes. SUMO proteins intervene in the progression of DN by modulating various signaling cascades, such as Nrf2-mediated oxidative stress, NF-κB, TGF-β, and MAPK pathways. Recent advancements indicate that natural products regulating SUMOylation hold promise as targets for intervening in DN. In a previous article published in 2022, we reviewed the mechanisms by which SUMOylation intervenes in renal fibrosis and presented a summary of some natural products with therapeutic potential. Therefore, this paper will focus on DN. The aim of this review is to elucidate the mechanism of action of SUMOylation in DN and related natural products with therapeutic potential, thereby summarising the targets and candidate natural products for the treatment of DN through the modulation of SUMOylation, such as ginkgolic acid, ginkgolide B, resveratrol, astragaloside IV, etc., and highlighting that natural product-mediated modulation of SUMOylation is a potential therapeutic strategy for the treatment of DN as a potential therapeutic strategy.

Tissue-specific activation of insulin signaling as a potential target for obesity-related metabolic disorders

The incidence of obesity is rapidly increasing worldwide. Obesity-associated insulin resistance has long been established as a significant risk factor for obesity-related disorders such as type 2 diabetes and atherosclerosis. Insulin plays a key role in systemic glucose metabolism, with the liver, skeletal muscle, and adipose tissue as the major acting tissues. Insulin receptors and the downstream insulin signaling-related molecules are expressed in various tissues, including vascular endothelial cells, vascular smooth muscle cells, and monocytes/macrophages. In obesity, decreased insulin action is considered a driver for associated disorders. However, whether insulin action has a positive or negative effect on obesity-related disorders depends on the tissue in which it acts. While an enhancement of insulin signaling in the liver increases hepatic fat accumulation and exacerbates dyslipidemia, enhancement of insulin signaling in adipose tissue protects against obesity-related dysfunction of various organs by increasing the capacity for fat accumulation in the adipose tissue and inhibiting ectopic fat accumulation. Thus, this "healthy adipose tissue expansion" by enhancing insulin sensitivity in adipose tissue, but not in the liver, may be an effective therapeutic strategy for obesity-related disorders. To effectively address obesity-related metabolic disorders, the mechanisms of insulin resistance in various tissues of obese patients must be understood and drugs that enhance insulin action must be developed. In this article, we review the potential of interventions that enhance insulin signaling as a therapeutic strategy for obesity-related disorders, focusing on the molecular mechanisms of insulin action in each tissue.

Prevalence, Clinical Characteristics, and Treatment of Patients with Resistant Hypertension: A Single-Center Study

BACKGROUND

Resistant hypertension (HTN) is associated with a high risk of cardiovascular complications. Our study aimed to assess the prevalence, characteristics, and treatment of patients with resistant HTN.

METHODS

We screened 4340 consecutive cardiovascular patients hospitalized in our clinic and identified 3762 with HTN. Of them, 128 fulfilled criteria for resistant HTN and were included in our study. We matched these patients to 128 hospitalized patients with controlled HTN.

RESULTS

Resistant HTN patients comprised 3.4% of all hypertensive individuals. Most of these patients (67.2%) were at high or very high cardiovascular risk compared to controlled HTN patients (40.6%); p < 0001. Resistant HTN patients more commonly had concomitant chronic kidney disease (CKD) (60.9%), overweight/obesity (52.3%), dyslipidemias (35.2%), smoking (27.3%), and diabetes (21.9%) compared to controlled HTN patients (37.5%, 29.7%, 28.1%, 14.1%, and 7.8%, respectively); p < 0.001. Regression analysis showed the strongest association of resistant HTN with CKD (OR 6.64), stage III HTN (OR 3.07), and obesity/overweight (OR 2.60). In contrast, single-pill combinations (SPCs) were associated with a lower likelihood of uncontrolled HTN (OR 0.58).

CONCLUSIONS

Resistant HTN represented a small proportion of all hypertensives in our study, but it was characterized by high/very high cardiovascular risk. Optimized therapy including increased use of SPCs could improve blood pressure control and long-term prognosis for these patients.

GLP-1-based therapies for the treatment of resistant hypertension in individuals with overweight or obesity: a review

Despite the availability of a wide range of antihypertensive agents, a significant proportion of individuals with resistant hypertension (RHTN) struggle to achieve blood pressure (BP) control. Obesity ranks among the most significant modifiable risk factors for RHTN, with 56-91% of patients with RHTN classified as overweight or obese. Glucagon-like peptide-1 receptor agonist (GLP-1 RAs) are a class of anti-obesity medications that have recently demonstrated efficacy in reducing BP and improving cardiovascular (CV) outcomes in individuals with overweight or obesity. Among the available GLP-1-based therapies, liraglutide, semaglutide, and tirzepatide have been approved for chronic weight management in this population. Tirzepatide, a dual GLP-1 and glucose-dependent insulinotropic polypeptide receptor agonist, has the greatest effect on weight loss and BP reduction compared to GLP-1 RAs alone. To our knowledge, no trials have directly evaluated the effect of GLP-1 RAs or dual GLP-1/GIP receptor agonists on RHTN management. In this review article, we propose that targeting weight loss through GLP-1-based therapies should be explored as a treatment option for individuals with RHTN who are overweight or obese.

Association between triglyceride-glucose index and hypertension: a cohort study based on the China Health and Nutrition Survey (2009-2015)

AIM

Insulin resistance (IR) may participate in the pathogenesis of hypertension by mediating low-grade systemic inflammation. The triglycerides-glucose (TyG) index has recently been suggested as a reliable alternative biochemical marker of IR compared with traditional methods. Herein, we speculated TyG index may also be associated with hypertension.

METHODS

Data of adults were extracted from the China Health and Nutrition Survey (CHNS) in 2009-2015 in this retrospective cohort study. The TyG index was calculated using the formula: TyG = Ln [fasting triglycerides (mg/dL) ×fasting glucose (mg/dL)/2]. Associations between TyG index and hypertension were evaluated by univariate and multivariate logistic regression analyses with odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses of age and gender were also performed. In addition, we assessed the interaction effect between TyG index and body mass index (BMI) on hypertension in participants with different age and gender.

RESULTS

Among 3,413 eligible participants, 1,627 (47.67%) developed hypertension. The average TyG index in hypertension group and non-hypertension group was 8.58 and 8.39 respectively. After adjusting for covariates, we found that compared with participants with TyG index ≤ 8.41 (median value), those who had higher TyG index seemed to have higher odds of hypertension [OR = 1.17, 95%CI: (1.01-1.37)]. Similarly, this association was also discovered in participants who aged ≤ 65 years old [OR = 1.19, 95%CI: (1.01-1.39)] or were female [OR = 1.35, 95%CI: (1.10-1.65)]. Additionally, there was a potential additive interaction effect between obesity and TyG index on hypertension.

CONCLUSION

High TyG index was associated with high odds of hypertension in general population in China, but the causal relationship between them needed further exploration.

Non-linear relationship between body roundness index and albuminuria among children and adolescents aged 8-19 years: A cross-sectional study

INTRODUCTION

Obesity has been found to be correlated with numerous health issues, including an elevated risk of albuminuria in adults. However, this correlation is still controversial among children and adolescents, as several recent large-scale cross-sectional studies have observed a negative correlation between obesity and albuminuria. Our study aimed to investigate the link between the body roundness index (BRI) and albuminuria among children and adolescents, in order to further understand the correlation between obesity and albuminuria in this demographic.

METHODS

We employed information from the National Health and Nutrition Examination Survey (NHANES) 1999-2010 for cross-sectional analysis. Weighted logistic regression was employed to explore the linear relationship between BRI and albuminuria, with subgroup analyses performed for more detailed insights. Weighted linear regression analysis was employed to explore the relationship between BRI and the urine albumin-creatinine ratio (UACR). Additionally, we applied smooth curve fitting to investigate their non-linear relationship and conducted threshold effect analysis to identify any turning point.

RESULTS

In this study of 15,487 participants aged 8-19 years, multivariate logistic regression analysis revealed a significant negative correlation between BRI and albuminuria (OR = 0.616, 95%CI: 0.526-0.722). The relationship between BRI and UACR, as shown by multivariate linear regression analysis, was significantly inversely correlated (β: -5.424, 95%CI: -7.416 to -3.433). Furthermore, smooth curve fitting and threshold effect analysis showed a non-linear relationship between BRI and albuminuria, with a BRI inflection point identified at 2.906.

CONCLUSIONS

These findings of our study suggest a significant nonlinear negative association between BRI and the presence of albuminuria among children and teenagers, and maintaining an appropriate BRI may decrease the occurrence of albuminuria in this population.

DNA Methylation Mediated the Association of Body Mass Index With Blood Pressure in Chinese Monozygotic Twins

Obesity is an established risk factor for hypertension, but the mechanisms are only partially understood. We examined whether body mass index (BMI)-related DNA methylation (DNAm) variation would mediate the association of BMI with blood pressure (BP). We first conducted a genomewide DNA methylation analysis in monozygotic twin pairs to detect BMI-related DNAm variation and then evaluated the mediating effect of DNAm on the relationship between BMI and BP levels using the causal inference test (CIT) method and mediation analysis. Ontology enrichment analysis was performed for CpGs using the GREAT tool. A total of 60 twin pairs for BMI and systolic blood pressure (SBP) and 58 twin pairs for BMI and diastolic blood pressure (DBP) were included. BMI was positively associated with SBP (β = 1.86, p = .0004). The association between BMI and DNAm of 85 CpGs reached p < 1×10-4 level. Eleven BMI-related differentially methylated regions (DMRs) within LNCPRESS1, OGDHL, RNU1-44P, NPHS1, ECEL1P2, LLGL2, RNY4P15, MOGAT3, PHACTR3, and BAI2 were found. Of the 85 CpGs, 9 mapped to C10orf71-AS1, NDUFB5P1, KRT80, BAI2, ABCA2, PEX11G and FGF4 were significantly associated with SBP levels. Of the 9 CpGs, 2 within ABCA2 negatively mediated the association between BMI and SBP, with a mediating effect of -0.24 (95% CI [-0.65, -0.01]). BMI was also positively associated with DBP (β = 0.60, p = .0495). The association between BMI and DNAm of 193 CpGs reached p < 1×10-4 level. Twenty-five BMI-related DMRs within OGDHL, POU4F2, ECEL1P2, TTC6, SMPD4, EP400, TUBA1C and AGAP2 were found. Of the 193 CpGs, 33 mapped to ABCA2, ADORA2B, CTNNBIP1, KDM4B, NAA60, RSPH6A, SLC25A19 and STIL were significantly associated with DBP levels. Of the 33 CpGs, 12 within ABCA2, SLC25A19, KDM4B, PTPRN2, DNASE1, TFCP2L1, LMNB2 and C10orf71-AS1 negatively mediated the association between BMI and DBP, with a total mediation effect of -0.66 (95% CI [-1.07, -0.30]). Interestingly, BMI might also negatively mediate the association between the DNAm of most CpG mediators mentioned above and BP. The mediating effect of DNAm was also found when stratified by sex. In conclusion, DNAm variation may partially negatively mediate the association of BMI with BP. Our findings may provide new clues to further elucidate the pathogenesis of obesity to hypertension and identify new diagnostic biomarkers and therapeutic targets for hypertension.

Role of dysfunctional peri-organ adipose tissue in metabolic disease

Metabolic disease is a complex disorder defined by a group with interrelated factors. There is growing evidence that obesity can lead to a variety of metabolic diseases, including diabetes and cardiovascular disease. Excessive adipose tissue (AT) deposition and ectopic accumulation can lead to increased peri-organ AT thickness. Dysregulation of peri-organ (perivascular, perirenal, and epicardial) AT is strongly associated with metabolic disease and its complications. The mechanisms include secretion of cytokines, activation of immunocytes, infiltration of inflammatory cells, involvement of stromal cells, and abnormal miRNA expression. This review discusses the associations and mechanisms by which various types of peri-organ AT affect metabolic diseases while addressing it as a potential future treatment strategy.

Glucose Metabolism Indices and the Development of Chronic Kidney Disease: A Cohort Study of Middle-Aged and Elderly Chinese Persons

Objective

Chronic kidney disease (CKD) has become a major global health issue, and abnormalities of glucose metabolism are a risk factor responsible for development of CKD. We aimed to investigate associations between glucose metabolism indices and CKD in a Chinese population and determine which index is superior for predicting incident CKD.

Methods

We performed a community-based population on 5232 subjects aged ≥40 years without baseline CKD. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 or urinary albumin-to-creatinine ratio (UACR) ≥30 mg/g. We examined the associations of glucose metabolism indices, including fasting plasma glucose (FPG), 2-hour (2 h) oral glucose tolerance test (OGTT), hemoglobin A1c (HbA1c), fasting insulin level, homeostasis model assessment of insulin resistance (HOMA-IR), and HOMA-β and the development of CKD.

Results

With an average follow-up of 3.6 years, 6.4% of the subjects developed CKD. Pearson's correlation analysis revealed that FPG, HbA1c, fasting insulin, and HOMA-IR were all significantly correlated with UACR and eGFR. The association persisted in multivariate linear regression analysis adjusted for age and sex. Compared with other glucose indices, HOMA-IR exhibited the strongest associations with CKD in COX multivariate regression analysis (HR = 1.17, 95% CI: 1.04-1.31).

Conclusion

HOMA-IR is superior to other routine indices of glucose metabolism for predicting the development of CKD in middle-aged Chinese persons. Screening with HOMA-IR may help prevent the development of CKD in the general population.

Triglyceride glucose-body mass index and hypertension risk in iranian adults: a population-based study

BACKGROUND

Insulin resistance (IR) and obesity are risk factors for hypertension; triglyceride-glucose (TyG) is known as a surrogate for IR. The present study investigated the association between the triglyceride-glucose body mass index (TyG-BMI) index and the risk of hypertension in Iranian adults.

METHODS

This study was conducted on a sample of 8,610 participants from the baseline phase of the Ravansar non- communicable diseases (RaNCD) in Iran. A logistic regression model was used to evaluate the relationship between TyG-BMI and hypertension. Receiver operating characteristic (ROC) curve analysis was conducted to estimate the predictive power of TyG-BMI for hypertension.

RESULTS

A total of 4176 men and 4434 women with an average age of 46.74 years were examined. The anthropometric indices were significantly higher in hypertensive than normotensive subjects (P < 0.001). The level of physical activity was significantly higher in the bottom quartiles (P < 0.001). The odds of hypertension in the highest quartile and 3.10 (95% CI: 2.28, 4.16) times significantly higher than the bottom quartile of the TyG-BMI index. The discriminating ability of TyG-BMI to predict blood pressure was 61% (AUC: 0.61; 95% CI: 0.57, 0.63), and higher than BMI and TyG.

CONCLUSION

The TyG-BMI index is associated with an increase in the odds of hypertension. Therefore, the TyG-BMI index can be a new clinical index for early diagnosis of hypertension. Lifestyle modifications such as weight control through physical activity and a healthy diet can help improve IR and prevent hypertension.

Determining the prevalence of childhood hypertension and its concomitant metabolic abnormalities using data mining methods in the Northeastern region of Hungary

Objective

Identifying hypertension in children and providing treatment for it have a marked impact on the patients' long-term cardiovascular outcomes. The global prevalence of childhood hypertension is increasing, yet its investigation has been rather sporadic in Eastern Europe. Therefore, our goal was to determine the prevalence of childhood hypertension and its concomitant metabolic abnormalities using data mining methods.

Methods

We evaluated data from 3 to 18-year-old children who visited the University of Debrecen Clinical Center's hospital throughout a 15-year study period (n = 92,198; boys/girls: 48/52%).

Results

We identified a total of 3,687 children with hypertension (2,107 boys and 1,580 girls), with a 4% calculated prevalence of hypertension in the whole study population and a higher prevalence in boys (4.7%) as compared to girls (3.2%). Among boys we found an increasing prevalence in consecutive age groups in the study population, but among girls the highest prevalences are identified in the 12-15-year age group. Markedly higher BMI values were found in hypertensive children as compared to non-hypertensives in all age groups. Moreover, significantly higher total cholesterol (4.27 ± 0.95 vs. 4.17 ± 0.88 mmol/L), LDL-C (2.62 ± 0.79 vs. 2.44 ± 0.74 mmol/L) and triglyceride (1.2 (0.85-1.69) vs. 0.94 (0.7-1.33) mmol/L), and lower HDL-C (1.2 ± 0.3 vs. 1.42 ± 0.39 mmol/L) levels were found in hypertensive children. Furthermore, significantly higher serum uric acid levels were found in children with hypertension (299.2 ± 86.1 vs. 259.9 ± 73.3 μmol/L), while glucose levels did not differ significantly.

Conclusion

Our data suggest that the calculated prevalence of childhood hypertension in our region is comparable to data from other European countries and is associated with early metabolic disturbances. Data mining is an effective method for identifying childhood hypertension and its metabolic consequences.

Obesity and chronic kidney disease

The prevalence of obesity has increased dramatically during the past decades, which has been a major health problem. Since 1975, the number of people with obesity worldwide has nearly tripled. An increasing number of studies find obesity as a driver of chronic kidney disease (CKD) progression, and the mechanisms are complex and include hemodynamic changes, inflammation, oxidative stress, and activation of the renin-angiotensin-aldosterone system (RAAS). Obesity-related kidney disease is characterized by glomerulomegaly, which is often accompanied by localized and segmental glomerulosclerosis lesions. In these patients, the early symptoms are atypical, with microproteinuria being the main clinical manifestation and nephrotic syndrome being rare. Weight loss and RAAS blockers have a protective effect on obesity-related CKD, but even so, a significant proportion of patients eventually progress to end-stage renal disease despite treatment. Thus, it is critical to comprehend the mechanisms underlying obesity-related CKD to create new tactics for slowing or stopping disease progression. In this review, we summarize current knowledge on the mechanisms of obesity-related kidney disease, its pathological changes, and future perspectives on its treatment.

Associations between triglyceride-glucose index and different hypertension subtypes: A population-based study in China

Background

Abnormal glycolipid metabolism plays a crucial role in hypertension. While an elevated triglyceride-glucose (TyG) index has been recognized as a risk factor for developing hypertension, the associations between the TyG index and different hypertension subtypes, namely, isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), and systolic-diastolic hypertension (SDH), remain unclear. This study was designed to investigate the associations between the TyG index and hypertension subtypes in a general Chinese population.

Materials and methods

In a sample of 16,793 participants from Shandong Province, China, multivariate logistic regression analyses were performed to examine the associations between the TyG index and different hypertension subtypes. Loess smooth curves were fitted to visualize the trends. Stratified analyses were conducted to further assess the potential interactions in the associations between the TyG index and different hypertension subtypes.

Results

A higher TyG index was associated with an increased odds of having IDH (OR = 2.94, 95% CI: 1.66–5.23) and SDH (OR = 1.82, 95% CI: 1.33–2.49), whereas no apparent relationship was observed between TyG index and ISH. With respect to sex, the effect of TyG index on having IDH and SDH was significant in women, but not in men. Participants with lower lipid profiles and glucose levels demonstrated a stronger strength of association between the TyG index and IDH as compared with the TyG index-SDH association. Stratified analysis showed that participants with a higher TyG index were more than 3 times more likely to have IDH and SDH among persons aged 18–42 years. Significant interactions were observed between TyG index and sex, age, and high-density lipoprotein cholesterol (HDL-C) in the SDH group, and a significant interaction was also found between TyG index and body mass index (BMI) in the ISH group.

Conclusion

Triglyceride-glucose index may potentially serve as a novel indicator for IDH and SDH. Our findings could also inform the development and implementation of targeted screening for hypertension.

Obesity-Related Chronic Kidney Disease: Principal Mechanisms and New Approaches in Nutritional Management

Obesity is the epidemic of our era and its incidence is supposed to increase by more than 30% by 2030. It is commonly defined as a chronic and metabolic disease with an excessive accumulation of body fat in relation to fat-free mass, both in terms of quantity and distribution at specific points on the body. The effects of obesity have an important impact on different clinical areas, particularly endocrinology, cardiology, and nephrology. Indeed, increased rates of obesity have been associated with increased risk of cardiovascular disease (CVD), cancer, type 2 diabetes (T2D), dyslipidemia, hypertension, renal diseases, and neurocognitive impairment. Obesity-related chronic kidney disease (CKD) has been ascribed to intrarenal fat accumulation along the proximal tubule, glomeruli, renal sinus, and around the kidney capsule, and to hemodynamic changes with hyperfiltration, albuminuria, and impaired glomerular filtration rate. In addition, hypertension, dyslipidemia, and diabetes, which arise as a consequence of overweight, contribute to amplifying renal dysfunction in both the native and transplanted kidney. Overall, several mechanisms are closely related to the onset and progression of CKD in the general population, including changes in renal hemodynamics, neurohumoral pathways, renal adiposity, local and systemic inflammation, dysbiosis of microbiota, insulin resistance, and fibrotic process. Unfortunately, there are no clinical practice guidelines for the management of patients with obesity-related CKD. Therefore, dietary management is based on the clinical practice guidelines for the nutritional care of adults with CKD, developed and published by the National Kidney Foundation, Kidney Disease Outcome Quality Initiative and common recommendations for the healthy population. Optimal nutritional management of these patients should follow the guidelines of the Mediterranean diet, which is known to be associated with a lower incidence of CVD and beneficial effects on chronic diseases such as diabetes, obesity, and cognitive health. Mediterranean-style diets are often unsuccessful in promoting efficient weight loss, especially in patients with altered glucose metabolism. For this purpose, this review also discusses the use of non-classical weight loss approaches in CKD, including intermittent fasting and ketogenic diet to contrast the onset and progression of obesity-related CKD.

Huoxue Qianyang Qutan Recipe Protects against Early Renal Damage Induced by Obesity-Related Hypertension via the SIRT1/NF-κB/IL-6 Pathway: Integrating Network Pharmacology and Experimental Validation-Based Strategy

Obesity is recognized as not only a major contributing factor to cardiovascular diseases but also an independent risk factor for end-stage renal disease. Previous studies have found that Huoxue Qianyang Qutan Recipe (HQQR) could reduce urinary microalbumin in patients with obesity-related hypertension (OBH). However, the renal protective activity of HQQR in OBH and its molecular targets involved remains ambiguous. In this work, we investigate the mechanism of HQQR against OBH-induced early renal damage using integrating network pharmacology and experimental validation-based strategy. First, via network pharmacology, IL-6 is identified as one of the key targets of HQQR against early renal damage in hypertension, and inhibition of inflammation is a crucial process. Second, in in vivo experiments, HQQR can lower blood pressure, lose weight, and restore metabolic abnormalities in OBH rats, which could be associated with the effects on protecting early renal damage. Finally, in the mechanism, HQQR increases SIRT1 mRNA and protein expression consistent with reduction of NF-κB acetylation and suppressed the p65-mediated inflammatory signaling pathway. As a result, HQQR robustly inhibits OBH-induced renal inflammation by reducing IL-6 mRNA and protein levels in the renal tissue and the release of IL-6 in serum of OBH rats. This study aims to provide a multimethod (network pharmacology-animal experiment) and multilevel (component-target-pathway) strategy for the prevention and treatment of OBH-induced target organ damage by traditional Chinese medicine.

Mulberry leaves ameliorate diabetes via regulating metabolic profiling and AGEs/RAGE and p38 MAPK/NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Mulberry leaves have been used as traditional hypoglycemic medicine-food plant for thousand years in China. According to traditional Chinese medicine theory, type 2 diabetes mellitus (T2DM) belongs to the category of XiaoKe. Presently, the research of mulberry leaf hypoglycemic and lipid-lowering direction is mature, but the curative effects of alkaloids, flavonoids, polysaccharides, and other bioactive ingredients and the related mechanism is still unclear.

AIM OF THE STUDY

This paper aims to study the efficacy and mechanism of alkaloids, flavonoids, polysaccharides, and other bioactive components in mulberry leaves in the treatment of T2DM individually.

MATERIALS AND METHODS

The determination of levels of fasting blood glucose (FBG), triglyceride (TG) and total cholesterol (T-Cho), and pyruvate kinase (PK), hexokinase (HK), and alanine aminotransferase (ALT/GPT) of in plasma of diabetic mice. Urine metabolomics was analyzed by UPLC-QTOF/MS to evaluate differential metabolites from multiple metabolic pathways. The glucose uptake of HepG2 cells and 3T3-L1 cells. Expression of Caspase-3 and caspase-9, inflammatory injury and p38MAPK/NF-κB signaling pathway in GLUTag cells.

RESULTS

Our study revealed alkaloids, flavonoids, and polysaccharides in mulberry leaf could increase the levels of PK, HK, and ALT/GPT, and decrease the levels of TG and T-Cho significantly, and regulate glucose, amino acid, and lipid metabolism. Furthermore, 1-deoxynojirimycin (DNJ) and isoquercitrin (QG) both could increase glucose uptake and promote differentiation of HepG2 cells, increase PPARγ, C/EBPα and SREBP-l expression in 3T3-L1 cells, and inhibit AGEs-induced injury and apoptosis in GLUTag cells, reduce the expression of proteins related to AGEs/RAGE and p38MAPK/NF-κB pathway. Notably, isoquercitrin exhibited more pronounced anti-diabetic efficacy.

CONCLUSIONS

The alkaloids, flavonoids, and polysaccharides from mulberry leaf exhibited hypoglycemic activity through the regulation of glucose, amino acid, and lipid metabolism. 1-DNJ and QG increased glucose uptake and promoted differentiation of HepG2 cells, increased PPARγ, C/EBPα and SREBP-l expression in 3T3-L1 cells, and inhibited AGEs-induced injury and apoptosis in GLUTag cells via the AGEs/RAGE and p38 MAPK/NF-κB pathway.

ANKRD36 Is Involved in Hypertension by Altering Expression of ENaC Genes

[Figure: see text].

Role of Renal Sympathetic Nerves in GLP-1 (Glucagon-Like Peptide-1) Receptor Agonist Exendin-4-Mediated Diuresis and Natriuresis in Diet-Induced Obese Rats

Background

The gut‐derived hormone GLP‐1 (glucagon‐like peptide‐1) exerts beneficial effects against established risk factors for chronic kidney disease. GLP‐1 influences renal function by stimulating diuresis and natriuresis and thus lowering arterial blood pressure. The role of the sympathetic nervous system has been implicated as an important link between obesity with elevated arterial pressure and chronic kidney disease. The primary aim of this study was to determine the contribution of renal sympathetic nerves on intrapelvic GLP‐1‐mediated diuresis and natriuresis in high‐fat diet (HFD)‐induced obese rats.

Methods and Results

Obesity was induced in rats by HFD for 12 weeks, followed by either surgical bilateral renal denervation or chronic subcutaneous endopeptidase neprilysin inhibition by sacubitril for a week. Diuretic and natriuretic responses to intrapelvic administration of the GLP‐1R (GLP‐1 receptor) agonist exendin‐4 were monitored in anesthetized control and HFD rats. Renal GLP‐1R expression and neprilysin expression and activity were measured. The effects of norepinephrine on the expression of GLP‐1R and neprilysin in kidney epithelial LLC‐PK1 cells were also examined. We found that diuretic and natriuretic responses to exendin‐4 were significantly reduced in the HFD obese rats compared with the control rats (cumulative urine flow at 40 minutes, 387±32 versus 650±65 µL/gkw; cumulative sodium excretion at 40 minutes, 42±5 versus 75±10 µEq/gkw, P<0.05). These responses in the HFD rats were restored after ablation of renal nerves (cumulative urine flow at 40 minutes, 625±62 versus 387±32 µL/gkw; cumulative sodium excretion at 40 minutes, 70±9 versus 42±5 µEq/gkw, P<0.05). Renal denervation induced significant reductions in arterial pressure and heart rate responses to intrapelvic GLP‐1 in the HFD rats. Renal denervation also significantly increased the GLP‐1R expression and reduced neprilysin expression and activity in renal tissues from the HFD rats. Chronic subcutaneous neprilysin inhibition by sacubitril increased GLP‐1–induced diuretic and natriuretic effects in the HFD rats. Finally, exposure of the renal epithelial cells to norepinephrine in vitro led to downregulation of GLP‐1R expression but upregulation of neprilysin expression and activity.

Conclusions

These results suggest that renal sympathetic nerve activation contributes to the blunted diuretic and natriuretic effects of GLP‐1 in HFD obese rats. This study provides significant novel insight into the potential renal nerve–neprilysin–GLP‐1 pathway involved in renal dysfunction during obesity that leads to hypertension.

Association Between Triglyceride-Glucose Index and Hypertension: A Meta-Analysis

Background: Triglyceride-glucose (TyG) index is a recently proposed surrogate indicator of insulin resistance. Previous studies evaluating the association between TyG index and hypertension risk in general adult population showed inconsistent results. We performed a meta-analysis to systematically evaluate this association. Methods: Observational studies, which evaluated the independent association between TyG index and hypertension in the general adult population, were identified by systematic search of PubMed, Embase, Web of Science, Wanfang data, and Chinese National Knowledge Infrastructure databases. A random-effect model, which incorporated the potential intra-study heterogeneity, was used for the meta-analysis. Results: Eight observational studies including 200,044 participants were included. Results showed that compared with those with the lowest category of TyG index, subjects with the highest category of TyG index were associated with higher odds of hypertension [adjusted risk ratio (RR): 1.53, 95% confidence interval (CI): 1.26-1.85, I ² = 54%, P < 0.001]. Sensitivity analysis by excluding one dataset at a time showed consistent result (adjusted RR: 1.44-1.62, P all < 0.001). Results of univariate meta-regression analysis showed that differences in sample size, mean age, male proportion, mean body mass index, and study quality score among the included studies did not have significant influence on the association between TyG index and hypertension (P values all > 0.10), suggesting that differences in these characteristics may not be the major source of heterogeneity. Subgroup analyses showed that study characteristics such as study design, participant ethnicity, age, or sex of the participants did not significantly affect the association (P for subgroup difference all >0.05). Conclusions: Higher TyG index may be associated with higher odds of hypertension in general adult population. Large-scale prospective cohort studies are needed to validate these findings, and further studies are needed to elucidate the potential pathophysiological mechanisms underlying the association between TyG index and hypertension.

Beneficial Effects of a Perindopril/Indapamide Single-Pill Combination in Hypertensive Patients with Diabetes and/or Obesity or Metabolic Syndrome: A Post Hoc Pooled Analysis of Four Observational Studies

INTRODUCTION

To assess real-life effectiveness of a perindopril/indapamide (Per/Ind) single-pill combination (SPC) in patients with hypertension (HT) and type 2 diabetes mellitus (T2DM), obesity and/or metabolic syndrome (MetS).

METHODS

This post hoc analysis pooled raw data from four large observational studies (FORTISSIMO, FORSAGE, ACES, PICASSO). Patients, most with uncontrolled blood pressure (BP) on previous treatments were switched to Per/Ind (10 mg/2.5 mg) SPC at study entry. Office systolic and diastolic blood pressures (SBP and DBP) were measured at baseline, 1 month and 3 months.

RESULTS

In the overall pooled population (N = 16,763), mean age was 61 ± 12 years, HT duration 11 ± 8 years, and baseline SBP/DBP 162/94 mmHg. T2DM, obesity and MetS were present in 21%, 49% and 27% of patients, respectively. Subgroups had similar mean age and HT duration to the overall population; patients with T2DM were slightly older (64 ± 10 years) with a longer HT duration (13 ± 8 years). Mean BP was approximately 160/95 mmHg in each subgroup. At 1 month, mean SBP decreased by approximately 20 mmHg in the overall population, and by a further 10 mmHg at 3 months. Similar results were observed in the three subgroups, with mean changes from baseline at 3 months of - 28 ± 15/- 13 ± 10 in T2DM; - 30 ± 15/- 14 ± 10 in obesity; and - 31 ± 15/- 15 ± 9 mmHg in MetS. BP decreases were greatest in patients with grade II or grade III HT. BP control rates (< 140/90 mmHg or 140/85 mmHg for T2DM) at 3 months were 59% in T2DM, 67% in obese, and 66% in MetS. No specific safety concerns were raised, particularly concerning ionic (Na, K) or metabolic profiles.

CONCLUSIONS

Switching to Per/Ind SPC led to rapid and effective BP decreases in patients with T2DM, obesity, or MetS. BP control was achieved in 6-7 out of 10 previously treated but uncontrolled patients. Treatment was well tolerated. The results confirm the beneficial effects of a Per/Ind SPC for difficult-to-control patient populations.

Association of triglyceride-glucose index and its interaction with obesity on hypertension risk in Chinese: a population-based study

Hypertension and triglyceride-glucose (TyG) index are both closely associated with insulin resistance, respectively, while the role of TyG index and the association between TyG index and obesity on hypertension risk remain unclear. This study aimed to examine the association and interactive effect of TyG index and obesity on hypertension risk. There was a population-based cross-sectional survey in Henan, China. Multivariate logistic regression analysis was performed to estimate the association between TyG index and the risk of prehypertension and hypertension. The area under curves (AUC) of TyG index and joint indicators (TyG index and obesity indices) was calculated to assess the predictive ability of hypertension. The additive interaction was computed to evaluate the interactive effect between TyG index and obesity. Compared with the lowest TyG quartile, participants in the highest quartile had an increased risk of prehypertension (odds ratio (OR): 1.69, 95% confidence interval (CI): 1.18-2.44) and hypertension (OR: 2.53, 95% CI: 1.80-3.57). The AUCs of joint indicators were significantly higher than TyG index in predicting hypertension (all P < 0.01). Presence of higher TyG index enhanced the ORs of waist-to-height ratio (WHtR) and percent body fat (PBF) from 3.50 (95% CI: 2.55-4.80) to 6.51 (95% CI: 4.81-8.82), and from 3.88 (95% CI: 2.78-5.42) to 7.09 (95% CI: 5.11-9.84) with significant additive interaction on hypertension, respectively. Increased TyG index was significantly associated with a higher risk of prehypertension and hypertension in Chinese adults. Besides, our results also demonstrated the interactions of TyG index and WHtR and PBF on hypertension risk.

Thioredoxin deficiency exacerbates vascular dysfunction during diet-induced obesity in small mesenteric artery in mice

OBJECTIVE

Thioredoxin (Trx) is a small cellular redox protein with established antioxidant and disulfide reductase properties. We hypothesized that Trx deficiency in mice would cause increased oxidative stress with consequent redox imbalance that would exacerbate obesity-induced vascular dysfunction.

METHODS

Non-transgenic (NT, C57BL/6) and dominant-negative Trx (dnTrx-Tg, low levels of redox-active protein) mice were either fed a normal diet (NC) or high fat diet plus sucrose (HFS) diet for 4 months (3-month HFD+ 1-month HFS). Weight gain, glucose tolerance test (GTT), insulin tolerance test (ITT), and other metabolic parameters were performed following NC or HFS diet. Arterial structural remodeling and functional parameters were assessed by myography.

RESULTS

Our study found that dnTrx mice with lower levels of active Trx exacerbated myogenic tone, inward arterial remodeling, arterial stiffening, phenylephrine-induced contraction, and endothelial dysfunction of MA. Additionally, FeTMPyP, a peroxynitrite decomposition catalyst, acutely decreased myogenic tone and contraction and normalized endothelial function in MA from dnTrx-Tg mice on HFS via increasing nitric oxide (NO)-mediated relaxation.

CONCLUSIONS

Our results indicate that deficiency of active Trx exacerbates MA contractile and relaxing properties during diet-induced obesity demonstrating that loss of redox balance in obesity is a key mechanism of vascular endothelial dysfunction.

Mesangial expansion at 5 years predicts death and death-censored graft loss after renal transplantation

Death with a functioning graft and death-censored renal allograft failure remain major problems for which effective preventative protocols are lacking. The retrospective cohort study aimed to determine whether histologic changes on a 5-year surveillance kidney biopsy predict adverse outcomes after transplantation in recipients who had: both Type 2 diabetes (T2DM) and obesity (BMI ≥ 30 kg/m² ) at the time of transplantation (T2DM/Obesity, n = 75); neither (No T2DM/No obesity, n = 78); No T2DM/Obesity (n = 41), and T2DM/No obesity (n = 47). On 5-year biopsies, moderate-to-severe mesangial expansion was more common in the T2DM/Obesity group (Banff mm score ≥2 = 49.3%; Tervaert classification MS ≥ 2b = 26.7%) compared to the other groups (p < .001 for both scores). Risk factors included older age, higher BMI, HbA1C, and triglycerides at 1-year post-transplant. Moderate-to-severe mesangial expansion correlated with death with function (HR 1.74 (1.01, 2.98), p = .045 Banff and 1.89 (1.01, 3.51) p = .045 Tervaert) and with death-censored graft loss (HR 3.2 (1.2, 8.8), p = .02 Banff and HR 3.8 (1.3, 11.5), p = .01 Tervaert) over a mean of 11.6 years of recipient follow-up post-transplant. These data suggest that mesangial expansion in recipients with T2DM and obesity may reflect systemic vascular injury and might be a novel biomarker to predict adverse outcomes post renal transplant.

Functional implications of vascular endothelium in regulation of endothelial nitric oxide synthesis to control blood pressure and cardiac functions

The endothelium is the innermost vascular lining performing significant roles all over the human body while maintaining the blood pressure at physiological levels. Malfunction of endothelium is thus recognized as a biomarker linked with many vascular diseases including but not limited to atherosclerosis, hypertension and thrombosis. Alternatively, prevention of endothelial malfunctioning or regulating the functions of its associated physiological partners like endothelial nitric oxide synthase can prevent the associated vascular disorders which account for the highest death toll worldwide. While many anti-hypertensive drugs are available commercially, a comprehensive description of the key physiological roles of the endothelium and its regulation by endothelial nitric oxide synthase or vice versa is the need of the hour to understand its contribution in vascular homeostasis. This, in turn, will help in designing new therapeutics targeting endothelial nitric oxide synthase or its interacting partners present in the cellular pool. This review describes the central role of vascular endothelium in the regulation of endothelial nitric oxide synthase while outlining the emerging drug targets present in the vasculature with potential to treat vascular disorders including hypertension.

Novel insight into perirenal adipose tissue: A neglected adipose depot linking cardiovascular and chronic kidney disease

Obesity is associated with adverse metabolic diseases including cardiovascular disease (CVD) and chronic kidney disease (CKD). These obesity-related diseases are highly associated with excess fat accumulation in adipose tissue. However, emerging evidence indicates that visceral adiposity associates more with metabolic and cardiovascular risk factors. Perirenal adipose tissue, surrounding the kidney, is originally thought to provides only mechanical support for kidney. However, more studies demonstrated perirenal adipose tissue have a closer association with renal disease than other visceral fat deposits in obesity. Additionally, perirenal adipose tissue is also an independent risk factor for CKD and even associated more with CVD. Thus, perirenal adipose tissue may be a connection of CVD with CKD. Here, we will provide an overview of the perirenal adipose tissue, a neglected visceral adipose tissue, and the roles of perirenal adipose tissue linking with CVD and CKD and highlight the perirenal adipose tissue as a potential strategy for future therapeutics against obesity-related disease.

Atorvastatin attenuates obese-induced kidney injury and impaired renal organic anion transporter 3 function through inhibition of oxidative stress and inflammation

An excessive consumption of high-fat diet can lead to the alterations of glucose and lipid metabolism, impaired insulin signaling and increased ectopic lipid accumulation resulting in renal lipotoxicity and subsequent renal dysfunction. Atorvastatin is a lipid-lowering drug in clinical treatment. Several studies have reported that atorvastatin has several significant pleiotropic effects including anti-inflammatory, antioxidant, and anti-apoptotic effects. However, the effects of atorvastatin on metabolic disturbance and renal lipotoxicity in obesity are not fully understood. In this study, obesity in rat was developed by high-fat diet (HFD) feeding for 16 weeks. After that, the HFD-fed rats were received either a vehicle (HF), atorvastatin (HFA) or vildagliptin (HFVIL), by oral gavage for 4 weeks. We found that HF rats showed insulin resistance, visceral fat expansion and renal lipid accumulation. Impaired renal function and renal organic anion transporter 3 (Oat3) function and expression were also observed in HF rats. The marked increases in MDA level, renal injury and NF-κB, TGF-β, NOX-4, PKC-α expression were demonstrated in HF rats. Atorvastatin or vildagliptin treatment attenuated insulin resistance and renal lipid accumulation-induced lipotoxicity in HFA and HFVIL rats. Moreover, the proteins involved in renal inflammation, fibrosis, oxidative stress and apoptosis were attenuated leading to improved renal Oat3 function and renal function in the treated groups. Interestingly, atorvastatin showed higher efficacy than vildagliptin in improving insulin resistance, renal lipid accumulation and in exerting renoprotective effects in obesity-induced renal injury and impaired renal Oat3 function.

Negative regulation of eNOS-NO signaling by over-SUMOylation of PPARγ contributes to insulin resistance and dysfunction of vascular endothelium in rats

SUMOylation of peroxisome proliferator-activated receptor gamma (PPAR γ) plays important regulatory role in its transcriptional activity. Our recent studies in vitro found that over-SUMOylation of PPARγ, like high glucose and high fat (HG/HF), induced endothelial insulin resistance (IR). However, whether such an event occurs in rats remains unclear. Therefore, our study aimed at investigating whether PPARγ over-SUMOylation could mimic high sucrose/fat diet (HFD) to induce endothelial IR and dysfunction and explored its underlying mechanisms. Normal chow-fed rats were intravenously infected with adenoviruses carrying the wild type cDNAs encoding PPARγ, SUMO1 and PIAS1 (protein inhibitor of activated STAT1). HFD-fed rats were regarded as a positive control. Body physical and biochemical parameters, glucose tolerance and vessel function were detected. The expression and SUMOylation levels of PPARγ were measured by western blotting and co-immunoprecipitation. Our results showed that like HFD, PPARγ over-SUMOylation induced endothelial IR and dysfunction via a negative regulation of eNOS-NO pathway. More importantly, we found that PPARγ over-SUMOylation induced endogenous SUMOylation cascade and exacerbated endothelial IR and dysfunction.The findings will deepen the understanding on PPARγ SUMOylation-regulating insulin signaling network and offer a potential target for prevention and cure of diabetic vascular complications.

Liraglutide Improves Renal Endothelial Function in Obese Zucker Rats on a High-Salt Diet

Metabolic syndrome is a common risk factor in chronic kidney disease. We investigated whether liraglutide [(LIRA), a glucagon-like peptide-1 receptor (GLP-1R) agonist] treatment improved renal vascular function and renal remodeling in male Zucker rats on a high-salt diet (6% NaCl). Zucker lean (+/+) and obese (fa/fa) rats (8 weeks old) were treated with vehicle or LIRA (0.1 mg/kg per day) for 8 weeks on a high-salt diet. The glomerular filtration rate (GFR) was measured at 0 and 8 weeks using the fluorescein isothiocyanate/sinistrin method in conscious rats. We used X-ray microangiography to measure renal arterial vessel diameter (70-350 µm) and vessel number in vivo in anesthetized rats. Renal protein expression levels of nitrotyrosine, CD-68, endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), transforming growth factor-β1, cyclooxygenase-2, and GLP-1R were assessed by western blotting. Renal gene expressions were determined by real-time polymerase chain reaction. In contrast to vehicle-treated rats, fa/fa-LIRA rats improved GFR, nitric oxide (NO)-mediated vasodilation in response to acetylcholine and sodium nitroprusside in small arterial vessels (<200 µm diameter). LIRA treatment increased vessel responsivity to NO donors in comparison with vehicle treatment. Increases in the expressions of proinflammatory, profibrotic, and oxidative stress related genes in fa/fa rats relative to +/+ were unaltered by LIRA, other than a trend toward attenuation of VCAM-1 gene expression. However, LIRA treatment increased protein expressions of eNOS (P = 0.014) and VEGF (P = 0.063), while reducing glomerular macrophage infiltration in comparison with vehicle-treated fa/fa rats. Low-dose LIRA treatment improved renal vascular function through amelioration of vascular dysfunction and improved NO-mediated dilation of small intrarenal arteries and arterioles and a reduction in renal inflammation.

Capsaicin in Metabolic Syndrome

Capsaicin, the major active constituent of chilli, is an agonist on transient receptor potential vanilloid channel 1 (TRPV1). TRPV1 is present on many metabolically active tissues, making it a potentially relevant target for metabolic interventions. Insulin resistance and obesity, being the major components of metabolic syndrome, increase the risk for the development of cardiovascular disease, type 2 diabetes, and non-alcoholic fatty liver disease. In vitro and pre-clinical studies have established the effectiveness of low-dose dietary capsaicin in attenuating metabolic disorders. These responses of capsaicin are mediated through activation of TRPV1, which can then modulate processes such as browning of adipocytes, and activation of metabolic modulators including AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor α (PPARα), uncoupling protein 1 (UCP1), and glucagon-like peptide 1 (GLP-1). Modulation of these pathways by capsaicin can increase fat oxidation, improve insulin sensitivity, decrease body fat, and improve heart and liver function. Identifying suitable ways of administering capsaicin at an effective dose would warrant its clinical use through the activation of TRPV1. This review highlights the mechanistic options to improve metabolic syndrome with capsaicin.

Glycated hemoglobin correlates with arterial stiffness and endothelial dysfunction in patients with resistant hypertension and uncontrolled diabetes mellitus

This study aimed to evaluate the effects of glycated hemoglobin (HbA_1c ) on flow-mediated dilation, intima-media thickness, pulse wave velocity, and left ventricular mass index in patients with resistant hypertension (RHTN) comparing RHTN-controlled diabetes mellitus and RHTN-uncontrolled type 2 diabetes mellitus. Two groups were formed: HbA_1c <7.0% (RHTN-controlled diabetes mellitus: n = 98) and HbA_1c ≥7.0% (RHTN-uncontrolled diabetes mellitus: n = 122). Intima-media thickness and flow-mediated dilation were measured by high-resolution ultrasound, left ventricular mass index by echocardiography, and arterial stiffness by carotid-femoral pulse wave velocity. No differences in blood pressure levels were found between the groups but body mass index was higher in patients with RHTN-uncontrolled diabetes mellitus. Endothelial dysfunction and arterial stiffness were worse in patients with RHTN-uncontrolled diabetes mellitus. Intima-media thickness and left ventricular mass index measurements were similar between the groups. After adjustments, multiple linear regression analyses showed that HbA_1c was an independent predictor of flow-mediated dilation and pulse wave velocity in all patients with RHTN. In conclusion, HbA_1c may predict the grade of arterial stiffness and endothelial dysfunction in patients with RHTN, and superimposed uncontrolled diabetes mellitus implicates further impairment of vascular function.

Association between blood cholesterol and sodium intake in hypertensive women with excess weight

Restricted sodium intake has been recommended for more than 1 century for the treatment of hypertension. However, restriction seems to increase blood cholesterol. In women with excess weight, blood cholesterol may increase even more because of insulin resistance and the high lipolytic activity of adipose tissue.The aim of this study was to assess the association between blood cholesterol and sodium intake in hypertensive women with and without excess weight.This was a cross-sectional study with hypertensive and nondiabetic women aged 20 to 59 years, recruited at the primary healthcare units of Maceio, Alagoas, Brazilian Northeast. Excess weight was defined as body mass index (BMI) ≥25.0 kg/m. Sodium intake was estimated by the 24-hour urinary excretion of sodium. Blood cholesterol was the primary outcome investigated by this study, and its relationship with sodium intake and other variables was assessed by Pearson correlation and multivariate linear regression using a significance level of 5%.This study included 165 hypertensive women. Of these, 135 (81.8%) were with excess weight. The mean sodium intake was 3.7 g (±1.9) and 3.4 g (±2.4) in hypertensive women with and without excess weight, respectively. The multiple normal linear regression models fitted to the "blood cholesterol" in the 2 groups reveal that for the group of hypertensive women without excess weight only 1 independent variable "age" is statistically significant to explain the variability of the blood cholesterol levels. However, for the group of hypertensive women with excess weight, 2 independent variables, age and sodium intake, can statistically explain variations of the blood cholesterol levels.Blood cholesterol is statistically inversely related to sodium intake for hypertensive women with excess weight, but it is not statistically related to sodium intake for hypertensive women without excess weight.

Preferred Fourth-Line Pharmacotherapy for Resistant Hypertension: Are We There Yet?

Resistant hypertension (RH) is defined as blood pressure (BP) that remains above target levels despite adherence to at least three different antihypertensive medications, typically including a diuretic. Epidemiological studies estimate that RH is increasing in prevalence, and is associated with detrimental health outcomes. The pathophysiology underlying RH is complex, involving multiple, overlapping contributors including activation of the renin-angiotensin aldosterone system and the sympathetic nervous system, volume overload, endothelial dysfunction, behavioural and lifestyle factors. Hypertension guidelines currently recommend specific pharmacotherapy for 1st, 2nd and 3rd-line treatment, however no specific fourth-line pharmacotherapy is provided for those with RH. Rather, five different antihypertensive drug classes are generally suggested as possible alternatives, including: mineralocorticoid receptor antagonists, α1-adrenergic antagonists, α2-adrenergic agonists, β-blockers, and peripheral vasodilators. Each of these drug classes vary in their efficacy, tolerability and safety profile. This review summarises the available data on each of these drug classes as a potential fourth-line drug and reveals a lack of robust clinical evidence for preferred use of most of these classes in the setting of RH. Moreover, there is a lack of direct comparative trials that could assist in identifying a preferred fourth-line pharmacologic approach and in providing evidence for hypertensive guidelines for adequate treatment of RH.

Transendothelial movement of adiponectin is restricted by glucocorticoids

Altered permeability of the endothelial barrier in a variety of tissues has implications both in disease pathogenesis and treatment. Glucocorticoids are potent mediators of endothelial permeability, and this forms the basis for their heavily prescribed use as medications to treat ocular disease. However, the effect of glucocorticoids on endothelial barriers elsewhere in the body is less well studied. Here, we investigated glucocorticoid-mediated changes in endothelial flux of Adiponectin (Ad), a hormone with a critical role in diabetes. First, we used monolayers of endothelial cells in vitro and found that the glucocorticoid dexamethasone increased transendothelial electrical resistance and reduced permeability of polyethylene glycol (PEG, molecular weight 4000 Da). Dexamethasone reduced flux of Ad from the apical to basolateral side, measured both by ELISA and Western blotting. We then examined a diabetic rat model induced by treatment with exogenous corticosterone, which was characterized by glucose intolerance and hyperinsulinemia. There was no change in circulating Ad but less Ad protein in skeletal muscle homogenates, despite slightly higher mRNA levels, in diabetic vs control muscles. Dexamethasone-induced changes in Ad flux across endothelial monolayers were associated with alterations in the abundance of select claudin tight junction (TJ) proteins. shRNA-mediated knockdown of one such gene, claudin-7, in HUVEC resulted in decreased TEER and increased adiponectin flux, confirming the functional significance of Dex-induced changes in its expression. In conclusion, our study identifies glucocorticoid-mediated reductions in flux of Ad across endothelial monolayers in vivo and in vitro This suggests that impaired Ad action in target tissues, as a consequence of reduced transendothelial flux, may contribute to the glucocorticoid-induced diabetic phenotype.

Cerebrovascular Disease: Consequences of Obesity-Induced Endothelial Dysfunction

Despite the well-known global impact of overweight and obesity in the incidence of cerebrovascular disease, many aspects of this association are still inconsistently defined. In this chapter we aim to present a critical review on the links between obesity and both ischemic and hemorrhagic stroke and discuss its influence on functional outcomes, survival, and current treatments to acute and chronic stroke. The role of cerebrovascular endothelial function and respective modulation is also described as well as its laboratory and clinical assessment. In this context, the major contributing mechanisms underlying obesity-induced cerebral endothelial function (adipokine secretion, insulin resistance, inflammation, and hypertension) are discussed. A special emphasis is given to the participation of adipokines in the pathophysiology of stroke, namely adiponectin, leptin, resistin, apelin, and visfatin.

Role of the Renal Microcirculation in Progression of Chronic Kidney Injury in Obesity

BACKGROUND

Obesity is largely responsible for the growing incidence and prevalence of diabetes, cardiovascular and renal diseases. Current strategies to prevent and treat obesity and its consequences have been insufficient to reverse the ongoing trends. Lifestyle modification or pharmacological therapies often produce modest weight loss which is not sustained and recurrence of obesity is frequently observed, leading to progression of target organ damage in many obese subjects. Therefore, research efforts have focused not only on the factors that regulate energy balance, but also on understanding mechanisms of target organ injury in obesity. Summary and Key Message: Microvascular (MV) disease plays a pivotal role in progressive kidney injury from different etiologies such as hypertension, diabetes, and atherosclerosis, which are all important consequences of chronic obesity. The MV networks are anatomical units that are closely adapted to specific functions of nutrition and removal of waste in every organ. Damage of the small vessels in several tissues and organs has been reported in obesity and may increase cardio-renal risk. However, the mechanisms by which obesity and its attendant cardiovascular and metabolic consequences interact to cause renal MV injury and chronic kidney disease are still unclear, although substantial progress has been made in recent years. This review addresses potential mechanisms and consequences of obesity-induced renal MV injury as well as current treatments that may provide protection of the renal microcirculation and slow progressive kidney injury in obesity.

Overnutrition, ectopic lipid and the metabolic syndrome

The metabolic syndrome is a constellation of metabolic risk factors including atherogenic dyslipidemia (elevated serum triglycerides, reduced high-density lipoprotein (HDL) cholesterol), elevated blood pressure, dysglycemia (insulin resistance and elevated serum glucose), a pro-inflammatory state, and a prothrombotic state. Most persons with metabolic syndrome are obese, and usually have abdominal obesity. Generally, obesity is a reflection of overnutrition. A current view is that when adipose tissue fails to store all excess nutrients as triglyceride, lipid begins to accumulate in various tissues (eg, muscle, liver, pancreas, and heart). This accumulation is called ectopic lipid. Various mechanisms have been proposed whereby ectopic lipid is detrimental in different tissues; these derangements induce metabolic risk factors. The foundation of the metabolic syndrome thus appears to be overnutrition, that is, more nutrient intake than can be safely disposed by lipid oxidation. Excess dietary carbohydrate also induces ectopic lipid. Of interest, less than half of obese individuals develop metabolic syndrome. Through various mechanisms they adapt to overnutrition so as to minimize lipid overload in tissues, and consequently, prevent the syndrome.

Clinical assessment of hypertension in children

The use of blood pressure measurements have become a routine part of physical exam for the evacuation of cardiovascular health adults and, more recently, children. The most widely used definition of hypertension is delineate as greater than 90 % BP according to age, sex, and height by the National High Blood Pressure Education Program. Current research suggests that pediatric hypertension is influenced by multitude of factors including birth weight, maturity during birth, heredity, and diet leading to primary hypertension. Factors influencing secondary hypertension include renal abnormalities, coarctation of the aorta, medications, neoplasm, etc. The treatment for pediatric hypertension is carried out with diet and exercise as the first line of defense. Only under non-compliance with diet and exercise is pharmaceutical intervention appropriate. This paper outlines a concise summary of the current understanding and research for scientists, clinicians, as well as for the general population to better understand pediatric hypertension.

A Larger Body Mass Index is Associated with Increased Atherogenic Dyslipidemia, Insulin Resistance, and Low-Grade Inflammation in Individuals with Metabolic Syndrome

BACKGROUND

The consequences of increased body mass index (BMI) on the metabolic disorders associated with metabolic syndrome (MetS) have not been thoroughly examined.

METHODS

We analyzed data from 262 individuals, 97 men and 165 women (aged 18-70 years), classified with MetS to investigate whether variations in BMI could be associated with parameters of dyslipidemia, insulin resistance, or low-grade inflammation. We hypothesized that increases in BMI would positively correlate with the major dysregulations in metabolism that define MetS. For this purpose, individuals were separated into four subgroups based on their BMI: normal weight (<25 kg/m(2)), overweight (≥25 to <30 kg/m(2)), obese (≥30 to <40 kg/m(2)), and morbidly obese (≥40 kg/m(2)).

RESULTS

As expected, body weight and waist circumference increased significantly as BMI increased (P < 0.0001). Both systolic and diastolic blood pressure were lower in the normal BMI group compared with the other three BMI groups (P = 0.001). Markers of HDL metabolism were adversely impacted in elevated BMI groups, as both high-density lipoprotein cholesterol (HDL-C) and large HDL decreased as BMI increased (P = 0.01). BMI was negatively correlated with HDL-C (r = -0.193, P = 0.002), HDL size (r = (-)0.227, P = 0.002), and large HDL (r = -0.147, P = 0.037). In addition, plasma insulin was highest in subjects classified as morbidly obese (P < 0.0001). There was also a strong positive correlation between BMI and plasma insulin (r = 0.413, P < 0.0001), whereas adiponectin, a marker of insulin sensitivity, was negatively correlated with BMI (r = -0.288, P = 0.001). Finally, BMI was positively correlated with proinflammatory C-reactive protein (r = 0.312, P = 0.0001) and interleukin-6 (r = 0.238, P = 0.001).

CONCLUSIONS

The data from this study suggest that the physiological factors associated with increased BMI exacerbate the metabolic abnormalities characteristic of MetS.