The metabolic syndrome and chronic kidney disease

Pharmacological Blockade of the Adenosine A2B Receptor Is Protective of Proteinuria in Diabetic Rats, through Affecting Focal Adhesion Kinase Activation and the Adhesion Dynamics of Podocytes

Induction of the adenosine receptor A2B (A2BAR) expression in diabetic glomeruli correlates with an increased abundance of its endogenous ligand adenosine and the progression of kidney dysfunction. Remarkably, A2BAR antagonism protects from proteinuria in experimental diabetic nephropathy. We found that A2BAR antagonism preserves the arrangement of podocytes on the glomerular filtration barrier, reduces diabetes-induced focal adhesion kinase (FAK) activation, and attenuates podocyte foot processes effacement. In spreading assays using human podocytes in vitro, adenosine enhanced the rate of cell body expansion on laminin-coated glass and promoted peripheral pY397-FAK subcellular distribution, while selective A2BAR antagonism impeded these effects and attenuated the migratory capability of podocytes. Increased phosphorylation of the Myosin2A light chain accompanied the effects of adenosine. Furthermore, when the A2BAR was stimulated, the cells expanded more broadly and more staining of pS19 myosin was detected which co-localized with actin cables, suggesting increased contractility potential in cells planted onto a matrix with a stiffness similar to of the glomerular basement membrane. We conclude that A2BAR is involved in adhesion dynamics and contractile actin bundle formation, leading to podocyte foot processes effacement. The antagonism of this receptor may be an alternative to the intervention of glomerular barrier deterioration and proteinuria in the diabetic kidney disease.

Composite dietary antioxidant index is associated with reduced prevalence of metabolic syndrome but not mortality in metabolic syndrome: Results from NHANES 2001-2018

The relationship between the composite dietary antioxidant index (CDAI), a comprehensive measure of individual dietary antioxidants, and the prevalence and mortality of metabolic syndrome (MetS) remains unknown. We aimed to explore these relationships in the National Health and Nutrition Examination Survey (NHANES). We explored these relationships using two independent cohorts. First, we addressed CDAI and the prevalence of MetS in the general population; second, we explored the association between CDAI and mortality in patients with MetS by following NHANES 2001-2018 participants through December 31, 2019. In addition, restricted cubic spline (RCS), stratified analysis, and sensitivity analysis were used for further interpretation. We included 24,514 participants aged 20-85 years, in which the prevalence of MetS was 27.61 %. CDAI was negatively and dose-responsively associated with the prevalence of MetS, however it was not associated with mortality in patients with MetS. In addition, CDAI was associated with a reduced prevalence of certain components of MetS, including dyslipidemia and central obesity. RCS showed a linear correlation between CDAI and MetS and the above components. Stratified analyses indicated that alcohol consumption was a significant influence of CDAI-MetS and that socioeconomic status and lifestyle specificity existed. Sensitivity analysis confirmed the stability of the results. CDAI was protective against the development of MetS in the general population, but not against mortality in patients with MetS. Clinicians need to develop individualized prevention strategies to reduce the development of MetS by modifying CDAI.

Prevalence of metabolic syndrome in patients with end-stage renal disease: a systematic review and meta-analysis

BACKGROUND

Metabolic syndrome, a significant risk factor for cardiovascular mortality in patients with end-stage renal disease, profoundly impacts patient prognosis and survival. Despite its clinical importance, the prevalence of metabolic syndrome remains unexplored in this population. Therefore, the objective of this study was to systematically assess the prevalence of metabolic syndrome among patients with end-stage renal disease and raise awareness among healthcare professionals.

METHODS

We conducted a comprehensive search in CNKI, WANFANG, WeiPu, CBM, PubMed, Web of Science, EMBASE, and The Cochrane Library databases. The search time was until August 21, 2023. Standardized tables were employed for data extraction and imported into Stata 16.0 software for subsequent meta-analysis. A random-effects model was employed to estimate combined prevalence and 95% confidence intervals. Subgroup and sensitivity analyses were conducted to explore potential sources of heterogeneity, while publication bias was evaluated using a funnel plot and Egger's test. This study has been registered with PROSPERO under the registration number CRD42023456284.

RESULTS

This meta-analysis comprised 35 studies involving a total of 14,202 participants. The pooled prevalence estimate for metabolic syndrome was 49.0% [95% CI (46.0,53.0)]. We conducted subgroup analyses based on participant characteristics, gender distribution, publication year, national economic status, diagnostic criteria employed, and components of metabolic syndrome.

CONCLUSIONS

The prevalence of metabolic syndrome is higher among patients with end-stage renal disease, necessitating early prevention and control measures to reduce its incidence and delay the progression of the disease, thereby improving patient life expectancy.

Renal transcriptome analysis of uninephrectomized db/db mice identified a mechanism for the transition to severe diabetic nephropathy

Diabetic nephropathy (DN), included in diabetic kidney disease (DKD), is a primary driver of end-stage renal disease (ESRD) leading to dialysis treatment. To develop new therapeutic drugs to prevent ESRD and avoid dialysis treatment, insight into DKD pathophysiology and animal models suitable for drug efficacy testing are needed. In this study, transcriptome analysis of kidneys from 26-week-old and 35-week-old uninephrectomized (UNX) db/db mice was used to identify the pathways that affect the deterioration of renal function in db/db mice. Differentially expressed genes suggested that there was increased interferon (IFN)-γ signaling during the 26 to 35-week period. Modules that changed between 26 and 35 weeks of age extracted by weighted gene co-expression network analysis (WGCNA) suggested increased the tumor necrosis factor (TNF)-α and nuclear factor-kappa B (NF-κB) signaling pathway in component cells of glomeruli. The protein-protein interaction (PPI) network analysis identified Cxcl16 as a hub gene for those signaling pathways, and it was shown that the pathways in this module changed when the glomerular filtration rate decreased in patients with DN. These results suggested the possibility that signaling mediated by Cxcl16 induced by IFN-γ and TNF-α between 26 and 35 weeks of age leads to renal fibrosis, resulting in severe disease. Drugs that target such pathways can be options for developing drugs for DN. We also think that the uninephrectomized db/db mouse can be used as an animal model of severe DKD and to evaluate efficacy in patients with DN.

Metabolic syndrome: imaging features and clinical outcomes

Metabolic syndrome, which affects around a quarter of adults worldwide, is a group of metabolic abnormalities characterized mainly by insulin resistance and central adiposity. It is strongly correlated with cardiovascular and all-cause mortality. Early identification of the changes induced by metabolic syndrome in target organs and timely intervention (eg, weight reduction) can decrease morbidity and mortality. Imaging can monitor the main components of metabolic syndrome and identify early the development and progression of its sequelae in various organs. In this review, we discuss the imaging features across different modalities that can be used to evaluate changes due to metabolic syndrome, including fatty deposition in different organs, arterial stiffening, liver fibrosis, and cardiac dysfunction. Radiologists can play a vital role in recognizing and following these target organ injuries, which in turn can motivate lifestyle modification and therapeutic intervention.

The Prevalence and Risk Factors of Metabolic Syndrome in Patients with Hemodialysis

Introduction

Metabolic syndrome is a common disorder that puts patients at high risk for cardiovascular disease (CVD) and mortality. To our knowledge, there is no published study in Pub Med which evaluated both lifestyle and metabolic syndrome in hemodialysis patients. This study aimed to estimate the prevalence of metabolic syndrome and investigate the potential risk factors in hemodialysis patients.

Methods

This was a cross-sectional study conducted on 204 patients enrolled conveniently. National Cholesterol Education Program Adult Treatment Panel III criteria considered for Metabolic Syndrome. Demographics, lifestyle, and disease characteristics were gathered. The relationship between metabolic syndrome and its severity with independent variables was investigated through multivariable multivariate logistic and linear regressions.

Results

The mean (SD) age was 55 (14) years and 42% were women. 42.6% had metabolic syndrome. Low high-density lipoprotein (HDL), high fasting blood sugar, high blood pressure (BP), increased waist circumference (WC), and high triglyceride were observed in decreasing order of frequency in 54.4%, 44.1%, 38.7%, 33.3% 28.9% of patients, respectively. The logistic regression model revealed significant associations between metabolic syndrome and physical activity (OR=0.85, 95% CI : 0.74-0.97), mood (OR=1.04, 95% CI : 1.002-1.078), age (OR=1.023, 95% CI : 1.001-1.046), and missed work (OR=0.86, 95% CI : 0.76-0.97). The linear regression model revealed significant associations between metabolic syndrome severity score and physical activity (B=-0.12, 95% CI : -0.21-0.02) and sleep quality (B=0.017, 95% CI : 0.001-0.033).

Conclusion

Poorer sleep quality, lower physical activity, lower mood status, and older age were associated with higher odds of metabolic syndrome/metabolic syndrome severity score in hemodialysis patients.

Metabolic syndrome and the risk of coronary artery disease among the physicians

Background

Physicians, due to their work and lifestyle patterns, can be at risk for metabolic syndrome (MetS). We aimed to evaluate the prevalence of MetS among physicians and its association with coronary artery disease (CAD).

Materials and methods

This retrospective cross-sectional study collected data on Thai physicians who had medical examination including cardiovascular testing from 14 February to 31 October 2022, in our hospital. Inclusion criteria were those who had complete data for MetS diagnosis per Adult Treatment Panel III criteria and CAD diagnosis information. Outcome measures were prevalence of MetS and CAD prevalence in affected vs non-affected physicians.

Results

Of 1194 physicians, the median age was 48.0±10.29 years. The authors found 4.5% were obese, 30.6% having high blood pressure, 26.6% high fasting blood sugar (FBS), 12.7% high triglycerides, and 13.7% low high-density lipoprotein (HDL). The prevalence of MetS was 8.9%. Increasing age, systolic blood pressure, body mass index, FBS, triglyceride, and decreasing HDL were identified as independent risk factors of MetS. The prevalence of CAD was 11.4%: 47.2% vs. 7.9% among the physicians with and without MetS respectively (odds ratio 10.41: 95% CI, 6.70-16.16%, P<0.001).

Conclusion

The prevalence of MetS among Thai physicians in this study was 8.9%. Those physicians with MetS were associated with a 10-fold higher risk of CAD. Physicians who were at risk of developing MetS should consider modifying their health habits and being vigilant about the potential consequences of CAD. Further prospective cohort studies are warranted to validate these results.

Components of metabolic syndrome as significant risk factors for postoperative complications following total shoulder arthroplasty: hypertension, diabetes, and obesity

Background

Metabolic syndrome (MetS) is a known risk factor for adverse postoperative outcomes. However, the literature surrounding the effects of MetS on orthopedic surgery outcomes following total shoulder arthroplasty (TSA) remains understudied. The purpose of this study is to investigate the effect of MetS on postoperative 30-day adverse outcomes following TSA.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent TSA between 2015 and 2020. After exclusion criteria, patients were divided into MetS and no MetS cohorts. MetS patients were defined as presence of hypertension, diabetes, and body mass index > 30 kg/m2. Bivariate logistic regression was used to compare patient demographics, comorbidities, and complications. Multivariate logistic regression, adjusted for all significant patient demographics and comorbidities, was used to identify the complications independently associated with MetS.

Results

A total of 26,613 patients remained after exclusion criteria, with 23,717 (89.1%) in the no MetS cohort and 2896 (10.9%) in the MetS cohort. On multivariate analysis, MetS was found to be an independent predictor of postoperative pneumonia (odds ratio [OR] 1.61, 95% confidence interval [CI] 1.02-2.55; P = .042), renal insufficiency (OR 4.09, 95% CI 1.67-10.00; P = .002), acute renal failure (OR 4.17, 95% CI 1.13-15.31; P = .032), myocardial infarction (OR 2.11, 95% CI 1.21-3.69; P = .009), nonhome discharge (OR 1.41, 95% CI 1.24-1.60; P < .001), and prolonged hospital stay > 3 days (OR 1.44, 95% CI 1.25-1.66; P < .001).

Conclusion

MetS was identified as an independent risk factor for postoperative pneumonia, renal insufficiency, acute renal failure, myocardial infarction, nonhome discharge, and prolonged hospital stay following TSA. These findings encourage physicians to medically optimize MetS patients prior to surgery to limit adverse outcomes.

Association of metabolic syndrome and chronic kidney disease

The prevalence of kidney disease is increasing rapidly worldwide, reflecting rising rates of obesity, diabetes, and associated metabolic syndrome (MetS). Chronic kidney disease and related comorbidities such as obesity, diabetes, and hypertension place a significant financial burden on healthcare systems. Despite the widespread use of RAAS inhibitors, intensive blood pressure and glycemic control, and newer therapeutic options consisting of sodium/glucose cotransporter-2 (SGLT-2) inhibitors or glucagon-like peptide-1 (GLP-1) receptor agonists, a significant risk of progression to end-stage renal disease remains in the high-risk obese and diabetic population. The MetS is a cluster of cardiovascular risk factors that adversely affect the development and progression of chronic kidney failure. According to the criteria of the World Health Organization, it is defined by visceral adiposity, impaired glucose tolerance or insulin resistance, atherogenic dyslipidemia, raised blood pressure, and microalbuminuria with a albumin-to-creatinine ratio ≥30 mg/g. At molecular level MetS is marked by a proinflammatory state and increased oxidative stress leading to various pathophysiological changes causing endothelial dysfunction and a hypercoagulable state. Because the kidney is a highly vascularized organ, it is especially susceptible for those microvascular changes. Therefore, the MetS and its individual components are associated with the premature development, acceleration, and progression of chronic kidney disease. Therefore, it is becoming increasingly important to elucidate the underlying mechanisms of MetS-associated chronic kidney disease in order to develop new strategies for preventing and slowing the progression of renal disease. In this review, we will elucidate (i) the renal structural, hemodynamic, and metabolic changes that occur in obesity and obesity-related kidney injury; (ii) the clinicopathological characteristics of obesity-related kidney injury, primarily focusing on obesity-associated glomerulopathy; (iii) the potential additional factors or predisposing factors that may turn patients more susceptible to renal structural or functional compensatory failure and subsequent injury.

Association between Neck Circumference and Chronic Kidney Disease in Korean Adults in the 2019-2021 Korea National Health and Nutrition Examination Survey

Chronic kidney disease (CKD) is a major public health problem and a leading cause of cardiovascular disease and death. Early recognition and management of CKD risk factors are necessary to prevent its onset and progression. Neck circumference (NC) is a non-invasive and easily accessible anthropometric measure associated with central obesity and subcutaneous fat accumulation in the upper body. Our study aimed to explore the relationship between NC and the prevalence of CKD using data from the nationally representative Korea National Health and Nutrition Examination Survey (2019-2021). We analyzed data from 10,219 subjects (age > 19 years, no missing values). CKD was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Logistic regression analysis was performed, which revealed a significant association between NC and CKD prevalence even after adjusting for confounding factors, both when NC was considered a continuous variable (OR [95% CI], 1.11 [1.03-1.19]) and in quartiles (Q1 as reference; Q2 OR [95% CI], 1.23 [0.91-1.67]; Q3 OR [95% CI], 1.59 [1.16-2.18]; Q4 OR [95% CI], 1.70 [1.16-2.50]). Our findings suggest that NC could be a simple and effective anthropometric measurement for identifying individuals at risk for CKD.

Protective effect of moringa seed extract on kidney damage in rats fed a high-fat and high-fructose diet

Objective

Moringa is a common plant that contains high levels of antioxidants. In this study, we aimed to analyze the protective effect of moringa seed extract on the kidneys of a rat model maintained on a high-fat and high-fructose (HFHF) diet.

Methods

An experiment with a pretest-posttest control group design was used to measure metabolic parameters and determine kidney function, while a posttest-only method was used for the control group to determine glomerular volume and superoxide dismutase (SOD) expression. Purposive sampling was used on 28 rats divided into four groups: a control (K1) group, and three groups fed a HFHF diet for 53 days (K2, K3, and K4). Subsequently, K3 and K4 were given 150 and 200 mg/kg BW per day moringa seed extract for 28 days. Data were analyzed using IBM® SPSS® Statistics version 22 software.

Results

Analysis showed that the diet increased the risk of metabolic syndrome, as evidenced by weight gain, glucose, and triglycerides. The optimal dose of moringa seed extract significantly improved glomerular volume (p = 0.001). The expression of SOD in kidney tubules and glomeruli was significantly different with each group (p = 0.002 and p = 0.001) respectively.

Conclusion

The administration of moringa seed extract provided a protective effect on the kidney by reducing serum creatinine levels, improving overall structure, and increasing the expression of SOD, a key antioxidant.

Butyrate alleviates renal inflammation and fibrosis in a rat model of polycystic ovarian syndrome by suppression of SDF-1

BACKGROUND

Polycystic ovarian syndrome (PCOS) is a multifactorial condition with metabolic-related complications, such as diabetic nephropathy and chronic renal disorder, which are the leading cause of renal transplant globally. Protective effects of histone deacetylase (HDAC) inhibitors (HDACi) have been documented in metabolic-linked pathologies. Nonetheless, the current study investigated the restorative role of HDACi, butyrate in experimental PCOS-induced renal disorder.

MATERIALS AND METHODS

Female Wistar rats (8-week-old) were divided into groups; control, butyrate-treated, letrozole and letrozole + butyrate-treated groups. To induce PCOS, 1 mg/kg of letrozole was given (oral gavage) for 21 days. After confirmation of PCOS, 200 mg/kg of butyrate (oral gavage) was administered for 6 weeks.

RESULTS

Rats with PCOS revealed disruption in glucose homeostasis (hyperinsulinemia and impaired glucose tolerance and insulin resistance) and presented with the phenotypes of PCOS (hyperandrogenism, multiple ovarian cysts and elevated LH/FSH ratio). Increased plasma and renal triglycerides and inflammatory (TNF-α/SDF-1/NF-κB) markers were observed with elevated levels of TGFβ-1, renal lipid peroxidation and redox imbalance (GGT, GSH, HIF-1α). Interestingly, animals with PCOS reported increased body weight as well as renal mass. Whereas, heightened levels of plasma urea, creatinine and creatine kinase indicating renal dysfunction, characterized by renal apoptosis (Caspase-6) and increased HDAC2 levels. Notwithstanding, administration of butyrate averted the alterations.

CONCLUSION

The present investigation demonstrates that PCOS declines renal function, which is accompanied by renal inflammation, apoptosis and fibrosis. The study further suggests that butyrate, an HDAC2i restores renal function by suppressing renal SDF-1 with subsequent attenuation of renal inflammation, apoptosis and fibrosis.

Metabolic Syndrome and Inflammation from Young to Mid-Adulthood and Subclinical Kidney Damage in Middle-Aged Australians

Background: Relationships between metabolic syndrome (MetS), inflammation, and chronic kidney disease (CKD) have been reported, but long-term follow-up studies are limited. This study aimed to investigate whether MetS and C-reactive protein (CRP) from young adulthood associated with the risk of subclinical kidney damage (SKD), a surrogate measure for CKD, in mid-adulthood. Materials and Methods: One thousand fifteen participants from the Childhood Determinants of Adult Health study aged 26-36 years at baseline (2004-2006) were followed up at age 36-49 (2014-2019). Log-binomial regression was used to determine whether MetS and high CRP in young adulthood and from young to mid-adulthood predicted the risk of SKD (an estimated glomerular filtration rate [eGFR] of 30-60 mL/min/1.73 m2 or an eGFR >60 mL/min/1.73 m2 with a urine albumin-creatinine ratio ≥2.5 mg/mmol [males] or ≥3.5 mg/mmol [females]) in midlife. Results: Having MetS in young adulthood was associated with an increased risk of SKD in midlife (adjusted relative risk [aRR] = 2.67, 95% confidence interval [CI]: 1.24-5.76). Participants with MetS and high CRP as young adults had a greater risk of having SKD in midlife (aRR = 4.27, 95% CI: 1.61-11.30) compared with those without MetS and high CRP. Furthermore, for participants with persistent MetS, the aRR of SKD in midlife was 4.08 (95% CI: 1.84-9.05) compared with those without MetS from young to mid-adulthood. No significant associations were found between CRP in young adulthood, or change in CRP from young to mid-adulthood, and SKD in midlife. Conclusions: MetS in young adulthood, with and without high CRP, and persistent MetS were associated with an increased risk of SKD in middle midlife.

Relationship between Phenotype Models Based on Waist Circumference and Triglyceride Levels and the Risk of Chronic Kidney Disease: A Systematic Review and Meta-analysis

Background

Chronic kidney disease (CKD) is a leading cause of death worldwide and has a high cost of treatment. Studies have indicated that a combination of waist circumference (WC) and triglyceride (TG) levels can be used to determine the risk of CKD. This study analyzes the risk of CKD using four phenotype models based on WC and TG.

Methods

This meta-analysis analyzes 113,019 participants from 13 studies. We conducted relevant literature searches in the Europe PMC, Medline, and Scopus databases using specific keywords. The results obtained were pooled into odds ratios (ORs) with 95% confidence intervals (CIs) using random-effects models.

Results

Our pooled analysis revealed that the highest significant independent association was between CKD and the high WC-high TG phenotype (adjusted OR, 1.61; 95% CI, 1.39 to 1.88; P<0.00001; I2=59%), followed by the high WC-normal TG phenotype (adjusted OR, 1.33; 95% CI, 1.12 to 1.57; P=0.001; I2=67%), and the normal WC-high TG phenotype (adjusted OR, 1.20; 95% CI, 1.06 to 1.37; P=0.005; I2=29%) when the normal WC-normal TG phenotype was taken as the reference.

Conclusion

Our study suggests that phenotype models based on WC and TG can be used as screening tools to predict the risk of CKD. Our results also indicate that WC plays a larger role than TG in the CKD risk. Further prospective studies are needed to confirm the results of our study.

Exposure to ambient air pollution and metabolic kidney diseases: evidence from the Northeast China Biobank

BACKGROUND

At present, there is no epidemiological evidence of the association between metabolic kidney diseases (MKD) and exposure to air pollution.

METHODS

We investigated the association between exposure to long-term air pollution and the risk of developing MKD using samples from the Northeast China Biobank.

RESULTS

Data from 29 191 participants were analyzed. MKD prevalence was 3.23%. Every standard deviation increment in PM2.5 increased the risk of MKD [odds ratio (OR) = 1.37, 95% confidence interval (CI) 1.19-1.58), diabetic kidney disease (DKD) (OR = 2.03, 95% CI 1.52-2.73), hypertensive kidney disease (BKD) (OR = 1.31, 95% CI 1.11-1.56), hyperlipidemic kidney disease (PKD) (OR = 1.39, 95% CI 1.19-1.63) and obese kidney disease (OKD) (OR = 1.34, 95% CI 1.00-1.81). PM10 increased the risk of MKD (OR = 1.42, 95% CI 1.20-1.67), DKD (OR = 1.38, 95% CI 1.03-1.85), BKD (OR = 1.30, 95% CI 1.07-1.58) and PKD (OR = 1.50, 95% CI 1.26-1.80). Sulfur dioxide increased the risk of MKD (OR = 1.57, 95% CI 1.34-1.85), DKD (OR = 1.81, 95% CI 1.36-2.40), BKD (OR = 1.44, 95% CI 1.19-1.74) and PKD (OR = 1.72, 95% CI 1.44-2.04). Ozone decreased the risk of PKD (OR = 0.83, 95% CI 0.70-0.99). Age, ethnicity and air pollution interacted to affect the risk of MKD, BKD and PKD. Associations between air pollution and CKD or metabolic disease were weaker than those with MKD. The association between air pollution and MKD became stronger when compared with participants with non-metabolic disease.

CONCLUSIONS

Air pollution may cause MKD or facilitate the progression from metabolic disease to renal failure.

Antioxidant and anti-inflammatory effects of allicin in the kidney of an experimental model of metabolic syndrome

Background

Recent studies have suggested that metabolic syndrome (MS) encompasses a group of risk factors for developing chronic kidney disease (CKD). This work aimed to evaluate the antioxidant and anti-inflammatory effects of allicin in the kidney from an experimental model of MS.

Methods

Male Wistar rats (220-250 g) were used, and three experimental groups (n = 6) were formed: control (C), metabolic syndrome (MS), and MS treated with allicin (16 mg/Kg/day, gastric gavage) (MS+A). MS was considered when an increase of 20% in at least three parameters (body weight, systolic blood pressure (SBP), fasting blood glucose (FBG), or dyslipidemia) was observed compared to the C group. After the MS diagnosis, allicin was administered for 30 days.

Results

Before the treatment with allicin, the MS group showed more significant body weight gain, increased SBP, and FBG, glucose intolerance, and dyslipidemia. In addition, increased markers of kidney damage in urine and blood. Moreover, the MS increased oxidative stress and inflammation in the kidney compared to group C. The allicin treatment prevented further weight gain, reduced SBP, FBG, glucose intolerance, and dyslipidemia. Also, markers of kidney damage in urine and blood were decreased. Further, the oxidative stress and inflammation were decreased in the renal cortex of the MS+A compared to the MS group.

Conclusion

Allicin exerts its beneficial effects on the metabolic syndrome by considerably reducing systemic and renal inflammation as well as the oxidative stress. These effects were mediated through the Nrf2 pathway. The results suggest allicin may be a therapeutic alternative for treating kidney injury induced by the metabolic syndrome risk factors.

Nonalcoholic Fatty Liver Disease and Chronic Kidney Disease Cross Talk

Nonalcoholic fatty liver disease is a multisystem condition with effects beyond the liver. The identification of chronic kidney disease as an independent mediator of nonalcoholic fatty liver disease or associated entity with shared cardiometabolic risk factors remains controversial and continues to draw scientific interest. With increasing prevalence of nonalcoholic fatty liver disease and lack of Food and Drug Administration approved therapies, these shared cardiometabolic risk factors have drawn significant attention. In this article, we review shared pathophysiological mechanisms between nonalcoholic fatty liver disease and chronic kidney disease along with current treatment strategies that might be useful for both disease processes.

The eGFR Decline as a Risk Factor for Metabolic Syndrome in the Korean General Population: A Longitudinal Study of Individuals with Normal or Mildly Reduced Kidney Function

Metabolic syndrome (MS) is a risk factor for the development and progression of chronic kidney disease (CKD). However, it is unclear whether decreased renal function affects MS. Through a longitudinal study, we investigated the effect of estimated glomerular filtration rate (eGFR) changes on MS in participants with an eGFR above 60 mL/min/1.73 m2. A cross-sectional (n = 7107) and a 14-year longitudinal study (n = 3869) were conducted to evaluate the association between MS and eGFR changes from the Korean Genome and Epidemiology Study data. The participants were categorized by their eGFR levels (60–75, 75–90, and 90–105 versus ≥ 105 mL/min/1.73 m2). In a cross-sectional analysis, the MS prevalence was significantly increased with a decline in the eGFR in a fully adjusted model. The odds ratio of individuals with an eGFR of 60–75 mL/min/1.73 m2 was observed to be the highest (2.894; 95% confidence interval (CI), 1.984–4.223). In the longitudinal analysis, incident MS significantly increased with an eGFR decline in all the models, with the highest hazard ratio in the lowest eGFR group (1.803; 95% CI, 1.286–2.526). In joint interaction analysis, all covariates showed a significant joint effect with an eGFR decline on the incident MS. MS incidents are associated with eGFR changes in the general population without CKD.

A Retrospective Evaluation of Changing Health Characteristics Amongst Deceased Organ Donors in the United States

BACKGROUND

The availability of suitable donor organs remains a limiting factor to performing life-saving transplant operations. This study evaluates changes in the health of the donor population and its influence on organ use in the United States.

METHODS

A retrospective analysis was performed using the OPTN STAR data file from 2005 to 2019. Three donor eras were defined: 1) 2005 to 2009, 2) 2010 to 2014, and 3) 2015 to 2019. The primary outcome was donor use, defined as transplantation of at least one solid organ. Descriptive analyses were performed, and associations of donor use were examined with multivariable logistic regression models. P values <.01 were considered significant.

RESULTS

The cohort included 132,783 potential donors of which 124,729 (93.9%) were used for transplantation. Donor median age was 42 years (interquartile range 26-54), 53,566 (40.3%) were female, and 88,209 (66.4%) were White, 21,834 (16.4%) were black, and 18,509 (13.9%) were Hispanic. Compared with donors from Eras 1 and 2, donors in Era 3 were younger (P < .001), had higher body mass index (BMI) (P < .001), increased rates of diabetes mellitus (DM) (P < .001), hepatitis C virus (HCV) positivity (P < .001) and more comorbidities (P < .001). Multivariable modeling found donor BMI, DM, hypertension, and HCV status as health factors significantly associated with donor use. Compared with Era 1, there was increased use in Era 3 of donors with BMI ≥30 kg/m², DM, hypertension, HCV-positive status, and donors with ≥3 comorbidities.

CONCLUSIONS

Despite an increasing prevalence of chronic health problems in the donor population, donors with multiple comorbid conditions are more likely to be used for transplantation in recent years.

Parathyroid diseases and metabolic syndrome

PURPOSE

Parathyroid diseases are related to parathyroid hormone (PTH) dysregulation by parathyroid cells or alteration of PTH function. They include hyperparathyroidism (PTH excess), hypoparathyroidism (PTH deficiency) and pseudohypoparathyroidism (PTH resistance). Little is known about correlation between parathyroid diseases and metabolic syndrome (MetS).

METHODS

An electronic-based search using PubMed was performed until October 2022 and articles were selected based on relevance of title, abstract, English language and publication in peer-reviewed journals.

RESULTS

Possible association between PTH alterations and the diverse manifestation of MetS have been proposed and it could be supposed that MetS may negatively influence parathyroid diseases. Available data show significant association for hyperparathyroidism and pseudohypoparathyroidism.

CONCLUSIONS

This review highlights the possible implications between MetS and parathyroid diseases. Given the increasing MetS global prevalence and the higher parathyroid diseases awareness and diagnosis, it may be interesting to further explore the possible role of alterations in parathyroid homeostasis in the development of MetS components with dedicated prospective studies.

Circulating Fibroblast Growth Factor-23 Levels Can Predict Rapid Kidney Function Decline in a Healthy Population: A Community-Based Study

BACKGROUND

Fibroblast growth factor-23 (FGF-23) associates with decreased kidney function in patients with chronic kidney disease (CKD). However, the correlation between circulating FGF-23 levels and the rate of renal function decline in healthy individuals is largely unknown. We aimed to evaluate the predictive performance of FGF-23 for rapid kidney function decline (RKFD) in a community-based study.

METHODS

A total of 2963 people residing in northern Taiwan were enrolled from August 2013 to May 2018 for an annual assessment of kidney function for five years. The baseline estimated glomerular filtration rates (eGFR) were calculated using the 2009 and 2021 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, which aggregates the values of serum creatinine and cystatin C (eGFRcr-cys). The outcome was RKFD-a 15% decrease in estimated glomerular filtration rate (eGFR) within the first four years, and a reduction in eGFR without improvement in the 5th year. A generalized additive model (GAM) was used to determine the cut-off value of FGF-23 to predict RKFD.

RESULTS

The incidence of RKFD was 18.0% (114/634). After matching for age and sex at a 1:1 ratio, a total of 220 subjects were analyzed. eGFRcr-cys was negatively correlated with total vitamin D level but seemed irrelevant to FGF-23. Multivariable logistic regression analysis showed that FGF-23, eGFRcr-cys, and urine albumin-to-creatinine ratio (UACR) were independent predictors of the possibility of RKFD. FGF-23 showed the best predictive performance for RKFD (AUROC: 0.803), followed by baseline eGFRcr-cys (AUROC: 0.639) and UACR (AUROC: 0.591). From the GAM, 32 pg/mL was the most appropriate cut-off value of FGF-23 with which to predict RKFD. The subgroup and sensitivity analyses showed consistent results that high-FGF-23 subjects had higher risks of RKFD.

CONCLUSIONS

Circulating FGF-23 level could be a helpful predictor for RKFD in this community-based population.

Prevalence and Predictors of Renal Disease in a National Representative Sample of the Romanian Adult Population: Data from the SEPHAR IV Survey

Background: The prevalence of chronic kidney disease (CKD) correlates with the prevalence of hypertension (HT). We studied the prevalence and predictors of CKD in a representative sample of the Romanian adult population. Methods: A sample of 1470 subjects were enrolled in the SEPHAR IV (Study for the Evaluation of Prevalence of Hypertension and Cardiovascular Risk) survey. All subjects were evaluated for blood pressure (BP) and extensive evaluations of target organ damage, blood, and urine samples were undertaken. Results: A total of 883 subjects were included in the statistical analysis. Those experiencing CKD with an eGFR < 60 mL/min/1.73 m2 were older at 71.94 ± 7.4 years (n = 19, 2.15%) compared with those without renal impairment at 50.3 ± 16.21 years (n = 864, 97.85%), p < 0.0001. The prevalence of CKD among hypertensives (379 from 883) was 4.49% (17/379), while 17 out of 19 subjects with CKD had HT (89.47%). After adjusting for age, sex, and diabetic status, only serum uric acid (SUR) > 6.9 mg/dL (OR: 6.61; 95% CI: 2.063, 10.83; p = 0.004) was an independent risk factor and a predictor of CKD. Conclusions: The prevalence of CKD in hypertensive Romanian adults was more than ten times higher than in the normotensive population. Levels of SUR > 6.9 mg/dL were predictors of CKD.

Gender differences in the association between insulin resistance and chronic kidney disease in a Chinese population with metabolic syndrome

BACKGROUND

Insulin resistance (IR) was reported to be associated with renal function impairment, but little is known about the gender difference. Hence, our study aimed to investigate the relationship between IR (estimated by the homeostasis model assessment of IR (HOMA-IR) index) and chronic kidney disease (CKD) in a Chinese population with metabolic syndrome (MetS) and discern whether there was any gender disparity or not.

METHODS

This retrospective cross-sectional study enrolled 13,638 men and 10,450 women who received health examinations from 2013 to 2016 at Xiamen Chang Gung Hospital. Among the participants, 3,253 men (64.3%) and 1,808 women (35.7%) who had MetS and met the inclusion criteria were included for analysis. Spearman's correlation was conducted to analyze the relationship between HOMA-IR and cardio-metabolic risk factors. Multivariable linear regression was analyzed to explore the relationship between HOMA-IR and cardio-metabolic variables. Logistic regression analysis was performed to assess the association between HOMA-IR and CKD.

RESULTS

The median HOMA-IR and prevalence of CKD was 2.2 and 11.31%, respectively, for men and 2.09 and 15.93%, respectively, for women. In multivariable linear regression analysis, HOMA-IR was significant associated with estimated GFR, albumin/creatinine ratio in men. Multivariable logistic regression revealed a significant difference between HOMA-IR value and the prevalence of CKD in men but not in women (odds ratio in male = 1.21; 95% CI 1.14-1.28, p ≤ 0.001; odds ratio in female = 1.01; 95% CI 0.99-1.02, p = 0.38).

CONCLUSIONS

HOMA-IR was independently associated with CKD among men with MetS but not in women.

Serum Cystatin C Levels Could Predict Rapid Kidney Function Decline in A Community-Based Population

BACKGROUND

Several biomarkers have been correlated with the prevalence and severity of chronic kidney disease (CKD); however, the association between biomarkers and rapid kidney function decline (RKFD) is unknown. This study aimed to evaluate the predictive performance of biomarkers to determine who is likely to develop RKFD in a healthy population.

METHODS

A community-based cohort of 2608 people residing in northern Taiwan were enrolled, and their renal function was followed annually from January 2014 to December 2019. The outcomes of interest were RKFD, defined as a 15% decrease in the estimated glomerular filtration rate (eGFR) within the first 4 years, and a decrease in eGFR without improvement in the fifth year. Clinical variables and potential predictors of RKFD, namely adiponectin, leptin, tumor necrosis factor-alpha, and cystatin C, were measured and analyzed.

RESULTS

The incidence of RKFD was 17.0% (105/619). After matching for age and sex at a 1:1 ratio, a total of 200 subjects were included for analysis. The levels of cystatin C and total vitamin D were significantly negatively correlated with eGFR. eGFR was negatively correlated with the levels of cystatin C and total vitamin D. Among the biomarkers, cystatin C showed the best predictive performance for RKFD (area under the receiver operating characteristic curve: 0.789). Lower serum cystatin C was associated with a higher rate of RKFD in healthy subjects. A generalized additive model showed that 0.82 mg/L was an adequate cut-off value of cystatin C to predict RKFD. Multivariable logistic regression analysis further indicated that low cystatin C and eGFR were independent predictors of the possibility of RKFD.

CONCLUSIONS

Serum cystatin C level could predict the possibility of RKFD. We suggest that a low cystatin C level should be considered as a risk factor for RKFD in healthy subjects.

Association between recovery/occurrence of metabolic syndrome and rapid estimated glomerular filtration rate decline in middle-aged and older populations: evidence from the China Health and Retirement Longitudinal Study

OBJECTIVES

Few studies have explored correlations between metabolic syndrome (MetS) alterations and renal deterioration in longitudinal cohorts. We aim to investigate associations between MetS recovery/development and rapid estimated glomerular filtration rate (eGFR) decline in the China Health and Retirement Longitudinal Study (CHARLS).

DESIGN

Longitudinal cohort study.

SETTING

This study is a secondary analysis of CHARLS.

PARTICIPANTS

After excluding individuals with age <45 years old, eGFR <60 mL/min/1.73 m² and clinician-reported malignant tumour, heart disease, stroke or kidney disease at baseline, 4142 participants with complete data were selected from the CHARLS during the 4-year follow-up period (2011-2015).

OUTCOME MEASURES

MetS were measured at 2011 and 2015 in CHARLS. A rapid eGFR decline was defined as an average annual eGFR decline of >3 mL/min/1.73 m². The associations between rapid eGFR decline and MetS recovery/development were analysed using multivariable adjusted logistic models.

RESULTS

According to MetS baseline status and follow-up, participants were divided into four groups: (1) 2460 (59.4%) in the MetS-free group, (2) 361 (8.7%) in the MetS-developed group, (3) 499 (12.0%) in the MetS recovery group and (4) 822 (19.8%) in the MetS chronic group. When compared with the MetS chronic group, the multivariable adjusted OR of rapid eGFR decline in the MetS recovery group was 0.64 (OR: 0.64; 95% CI 0.45 to 0.90, p=0.01). In contrast, when compared with the MetS-free group, the multivariable adjusted OR of rapid eGFR decline in the MetS-developed group was 1.00 (OR: 1.00; 95% CI 0.73 to 1.38, p=0.98).

CONCLUSIONS

Over the 4-year follow-up period, we found that MetS recovery was associated with a reduced risk of rapid eGFR decline in middle-aged and older adults, while MetS occurrence was not related to rapid eGFR decline. Recovery from MetS appeared to protect against a rapid decline in eGFR.

Novel Insights in the Physiopathology and Management of Obesity-Related Kidney Disease

Obesity is recognized as an independent risk factor for the development of kidney disease, which has led to the designation of obesity-related glomerulopathy (ORG). Common renal features observed in this condition include glomerular hypertrophy, glomerulosclerosis, haemodynamic changes and glomerular filtration barrier defects. Additionally, and although less studied, obesity-related kidney disease also involves alterations in renal tubules, including tubule hypertrophy, lipid deposition and tubulointerstitial fibrosis. Although not completely understood, the harmful effects of obesity on the kidney may be mediated by different mechanisms, with alterations in adipose tissue probably playing an important role. An increase in visceral adipose tissue has classically been associated with the development of kidney damage, however, recent studies point to adipose tissue surrounding the kidney, and specifically to the fat within the renal sinus, as potentially involved in the development of ORG. In addition, new strategies for the treatment of patients with obesity-related kidney disease are focusing on the management of obesity. In this regard, some non-invasive options, such as glucagon-like peptide-1 (GLP-1) receptor agonists or sodium–glucose cotransporter-2 (SGLT2) inhibitors, are being considered for application in the clinic, not only for patients with diabetic kidney disease but as a novel pharmacological strategy for patients with ORG. In addition, bariatric surgery stands as one of the most effective options, not only for weight loss but also for the improvement of kidney outcomes in obese patients with chronic kidney disease.

Hyperuricemia, a Non-Independent Component of Metabolic Syndrome, Only Predicts Renal Outcome in Chronic Kidney Disease Patients without Metabolic Syndrome or Diabetes

Uric acid (UA) is elevated in metabolic syndrome (MS) and diabetes (DM). UA is associated with central obesity and blood glucose and is proposed as a criterion of MS. Previous reports showed that UA could predict renal outcome in CKD. However, recent clinical trials did not demonstrate the benefits of urate-lowering agents (ULA) for renal outcome. Whether the prognostic value of UA for renal outcome is independent of MS or secondary to MS in CKD patients is unknown. Our study included 2500 CKD stage 1−4 Asian patients divided by UA tertiles and MS/DM. In linear regression, UA was associated with obesity, C-reactive protein, and renal function. In Cox regression, high UA was associated with worse renal outcome in non-MS/DM, but not in MS/DM: hazard ratio (95% confidence interval) of UA tertile 3 was 3.86 (1.87−7.97) in non-MS/DM and 1.00 (0.77−1.30) in MS/DM (p for interaction < 0.05). MS was associated with worse renal outcome, but redefined MS (including hyperuricemia as the 6th criteria) was not. In conclusion, hyperuricemia is associated with worse renal outcome in non-MS/DM and is not an independent component of MS in CKD stage 1−4 patients. Hyperuricemia secondary to MS could not predict renal outcome.

Metabolic Syndrome (MetS), Systemic Inflammatory Response Syndrome (SIRS), and Frailty: Is There any Room for Good Outcome in the Elderly Undergoing Emergency Surgery?

Background

Patients with MetS or SIRS experience higher rates of mortality and morbidity, across both cardiac and noncardiac surgery. Frailty assessment has acquired increasing importance in recent years as it predisposes elderly patients to a worse outcome. The aim of our study was to investigate the influence of MetS, SIRS, and with or without frailty on elderly patients undergoing emergency surgical procedures.

Methods

We analyzed data of all patients with nonmalignant diseases requiring an emergency surgical procedure from January 2017 to December 2020. The occurrence of MetS was identified using modified definition criteria used by the NCEP-ATP III Expert Panel: obesity, hypertension, diabetes, or if medication for high triglycerides or for low HDL cholesterol was taken. Systemic inflammatory response syndrome (SIRS) was evaluated according to the original consensus study (Sepsis-1). The frailty profile was investigated by the 5-modified Frailty Index (5-mFI) and the Emergency Surgery Frailty Index (EmSFI). Postoperative complications have been reported and categorized according to the Clavien-Dindo (C-D) classification system. Morbidity and mortality have been mainly considered as the 30-day standard period definition.

Results

Of the 2,318 patients included in this study, 1,010 (43.6%) fulfilled the criteria for MetS (MetsG group). Both 5-Items score and EmsFI showed greater fragility in patients with MetS. All patients with MetS showed more frequently a CACI index greater than 6. The occurrence of SIRS was higher in MetSG. LOS was longer in patients with MetS (MetSG 11.4 ± 12 days vs. n-MetSG 10.5 ± 10.2 days, p = 0.046). MetSG has a significantly higher rate of morbidity (353 (35.%) vs. 385 (29.4%), p = 0.005). The mortality rate in patients with MetS (98/1010, 10%) was similar to that in patients without it (129/1308, 10%). Considering patients with MetS who developed SIRS and those who had frailty or both, the occurrence of these conditions was associated with a higher rate of morbidity and mortality.

Conclusion

Impact of MetS and SIRS on elderly surgical patient outcomes has yet to be fully elucidated. The present study showed a 43.6% incidence of MetS in the elderly population. In conclusion, age per se should be not considered anymore as the main variable to estimate patient outcomes, while MetS and Frailty should have always a pivotal role.

Transition of Metabolic Phenotypes and Risk of Atrial Fibrillation According to BMI: Kailuan Study

Objective

Atrial fibrillation (AF) is associated with both obesity and its metabolic consequences. However, there is a paucity of information on whether the dynamic change of metabolic health and obesity phenotypes affect the risk of AF. We aimed to prospectively examine the association between metabolic health and its change over time and AF risk across body mass index (BMI) categories.

Methods

A total of 58,483 participants without history of cancer, and cardiovascular diseases from the Kailuan study were included in the present study. Transition of metabolic phenotypes was evaluated between 1st survey (2006–2007) and the 2nd survey (2008–2009). The hazard ratios (HRs) and 95% confidence intervals (CIs) for AF were assessed by Cox proportional hazards regression.

Results

During a median follow-up of 3 years, we documented 580 cases of AF. Compared with metabolically healthy individuals with normal weight, the multivariable-adjusted hazard ratios for metabolically healthy and unhealthy overweight/obese were 1.27 (95% CI: 1.01, 1.59) and 1.37 (95% CI: 1.09, 1.72), respectively. However, when transition was taken into account, overweight/obese people who maintained metabolically healthy status were not associated with increased long-term risk (HR, 1.11;95% CI: 0.70, 1.78), whereas participants who converted from metabolically healthy overweight/obese status to an unhealthy phenotype had higher AF risk than those who maintained metabolically healthy normal weight (HR 1.59, 95% CI: 1.11, 2.26). When BMI and metabolically healthy status were updated over the course of the study, significant short-term elevations in AF risk were associated with individuals with stable MU-OW/OB status.

Conclusion

In this community-based cohort study, metabolically healthy overweight/obese individuals have increased risks of AF. Obesity remains a risk factor for AF independent of major metabolic factors. Our data further suggested that metabolic phenotype was a dynamic condition, and maintenance of metabolic health and normal weight might alleviate the risk of AF.

Aerobic exercise training combined or not with okra consumption as a strategy to prevent kidney changes caused by metabolic syndrome in Zucker rats

The complications of Metabolic Syndrome (MetS) include kidney disease, and most dialysis patients are diagnosed with MetS. The benefit of exercise training (ET) for MetS treatment is already well defined in the literature, but the antidiabetic and antihyperlipidemic benefits of okra (O) have been discovered only recently. The aim of this study was to evaluate the effects of O and/or ET supplementation on renal function and histology; serum urea and creatinine value; inflammation (IL-6, IL-10, TNF-α) and oxidative stress in renal tissue. For this, 32 Zucker rats (fa/fa) were randomly separated into four groups of 8 animals each: Metabolic Syndrome (MetS), MetS + Okra (MetS + O), MetS + Exercise Training (MetS + ET), and MetS + Exercise Training and Okra (MetS + ET + O), and 8 Zucker lean (fa/+) rats comprised the Control group (CTL). Okra was administered by orogastric gavage 2x/day (morning and night, 100 mg/kg) and ET performed on the treadmill, at moderate intensity, 1h/day, 5x/week for 6 weeks. Although the renal function was not altered, the animals with MetS showed greater fibrotic deposition accompanied by a worse stage of renal injury, in addition to increased kidney weight. Although all interventions were beneficial in reducing fibrosis, only ET combined with O was able to improve the degree of renal tissue impairment. ET improved the anti-inflammatory status and reduced nitrite levels, but the combination of ET and O was more beneficial as regards catalase activity. Okra consumption alone did not promote changes in inflammatory cytokines and oxidative stress in the kidney. In conclusion, ET combined or not with O seems to be beneficial in preventing the progression of renal disease when renal function is not yet altered.

Relationships Between Metabolic Body Composition Status and Rapid Kidney Function Decline in a Community-Based Population: A Prospective Observational Study

Obesity and metabolic syndrome are strong risk factors for incident chronic kidney disease (CKD). However, the predictive accuracy of metabolic body composition status (MBCS), which combines the status of obesity and metabolic syndrome, for rapid kidney function decline (RKFD) is unclear. The aim of this study was to investigate the relationship between MBCS and RKFD in a healthy population in a prospective community-based cohort study. In the current study, we followed changes in renal function in 731 people residing in northern Taiwan for 5 years. The participants were divided into four groups according to their MBCS, including metabolically healthy normal weight (MHNW), metabolically healthy overweight (MHOW), metabolically unhealthy normal weight (MUNW), and metabolically unhealthy overweight (MUOW). We evaluated traditional risk factors for CKD and metabolic profiles. The primary outcome was RKFD, which was defined as a 15% decline in estimated glomerular filtration rate (eGFR) within the first 4 years, and a reduction in eGFR which did not improve in the 5th year. During the study period, a total of 731 participants were enrolled. The incidence of RKFD was 17.1% (125/731). Multiple Cox logistic regression hazard analysis revealed that age, cerebrovascular accident, eGFR, urine albumin-to-creatinine ratio, use of painkillers, depressive mood, MUNW and MUOW were independent predictors of RKFD. After adjusting for age, sex, eGFR and total cholesterol, the participants with MUNW and MUOW had higher hazard ratios (HRs) for RKFD [HR: 2.19, 95% confidence interval (CI): 1.22–3.95 for MUNW; HR: 1.86, 95% CI: 1.21–2.87 for MUOW] than those with MHNW. Similar results were also observed in subgroup analysis of those aged above 65 years. On the basis of the results of this study, we conclude that MBCS was independently associated with RKFD, especially in the older adults. On the basis of our results, we suggest that MUNW and MUOW should be considered as risk factors for RKFD.

Enzymatic hydrolysate of porphyra enhances the intestinal mucosal functions in obese mice

Intestinal mucosal immunity is important to human body; however, obesity induced by high-fat diet may bring a series of problems, such as chronic inflammation which may damage intestinal mucosal immunity. In this study, the effects of two different enzymatic hydrolysates of porphyra on the function of intestinal mucosal were explored in obese mice. The results showed that 10 consecutive weeks of high-fat dietary intake resulted in weight gain and intestinal abnormalities in C57BL/6 mice. However, the administration of enzymatic hydrolysate of porphyra effectively protected the intestinal mucosa from these injuries while reducing levels of oxidative stress (MDA, GSH, and GSH-Px). Specifically, they were found to improve small intestine morphological structure, increase growth of goblet cells and mucous, raise expression levels of lysozyme, and stimulate SIgA secretion, especially in the group administered with the enzymatic hydrolysate containing protease and polysaccharide enzyme (EHPP). The results showed that the enzymatic hydrolysates of porphyra may provide a protective measure to maintain intestinal mucosal barriers, which is beneficial to overall health. Porphyra is widely distributed all over the world. Moreover, an increasing number of studies have described its diverse biological functions. Therefore, it is necessary to find a way to develop products related to porphyra. In this study, a new type of polysaccharide enzyme of porphyra found in our previous research was used to make a clear porphyra energy drink with a lower molecular weight polysaccharide. Our findings highlighted the repaired intestinal barriers in obese bodies after the treatment with the enzymatic hydrolysate. PRACTICAL APPLICATIONS: Porphyra is widely distributed all over the world. Moreover, an increasing number of studies have described its diverse biological functions. Therefore, it is necessary to find a way to develop products related to porphyra. In this study, a new type of polysaccharide enzyme of porphyra found in our previous research was used to make a clear porphyra energy drink with a lower molecular weight polysaccharide. Our findings highlighted the repaired intestinal barriers in obese bodies after the treatment with the enzymatic hydrolysate.

Pathophysiological Analysis of Uninephrectomized db/db Mice as a Model of Severe Diabetic Kidney Disease

Diabetic nephropathy, included in diabetic kidney disease (DKD), is the primary disease leading to end-stage renal disease (ESRD) or dialysis treatment, accounting for more than 40% of all patients with ESRD or receiving dialysis. Developing new therapeutics to prevent the transition to ESRD or dialysis treatment requires an understanding of the pathophysiology of DKD and an appropriate animal model for drug efficacy studies. In this study, we investigated the pathophysiology of diabetic kidney disease with type 2 diabetes in uninephrectomized db/db mice. In addition, the nephrectomized db/db mice from 10 weeks to 42 weeks were used to assess the efficacy of long-term administration of the angiotensin-II–receptor antagonist losartan. The blood and urinary biochemical parameters and the blood pressure which is a main pharmacological endpoint of the losartan therapy, were periodically measured. And at the end, histopathological analysis was performed. Uninephrectomized db/db mice clearly developed obesity and hyperglycemia from young age. Furthermore, they showed renal pathophysiological changes, such as increased urinary albumin-creatinine ratio (UACR) (the peak value 3104±986 in 40-week-old mice), glomerular hypertrophy and increased fibrotic areas in the tubulointerstitial tubules. The blood pressure in the losartan group was significantly low compared to the normotensive Vehicle group. However, as expected, Losartan suppressed the increase in UACR (829±500) indicating the medication was sufficient, but the histopathological abnormalities including tubular interstitial fibrosis did not improve. These results suggest that the uninephrectomized db/db mice are useful as an animal model of the severe DKD indicated by the comparison of the efficacy of losartan in this model with the efficacy of losartan in clinical practice.

Soy Phospholipids Exert a Renoprotective Effect by Inhibiting the Nuclear Factor Kappa B Pathway in Macrophages

Complications associated with chronic kidney disease (CKD), which involves kidney inflammation, are a major health problem. Soy protein isolate (SPI) reportedly inhibits CKD exacerbation; however, its detailed action mechanism remains obscure. Therefore, the role of the polar lipid component of SPI in suppressing inflammation was investigated. Zucker fatty rats were divided into three groups and fed a diet containing casein, SPI, or casein + SPI ethanol extract (SPIEE) for 16 weeks. The isoflavones and phospholipids of SPIEE were evaluated for their anti-inflammatory effects. Rats in the SPI and casein + SPIEE groups showed reduced levels of the urinary N-acetyl-β-d-glucosaminidase and renal IL-1β mRNA (an inflammatory marker) compared with those in the casein group. In proximal tubular cells, genistein significantly inhibited monocyte chemoattractant protein-1 (MCP-1) expression induced by an IL-1β stimulus. In macrophages, soybean phospholipids suppressed lipopolysaccharide-induced IL-1β gene expression by inhibiting the phosphorylation of inhibitor κB and p65. Phosphatidylinositol (PI) was found to be essential for inhibition of IL-1β expression. SPIEE inhibited the exacerbation of kidney disease. Genistein and soybean phospholipids, especially soybean-specific phospholipids containing PI, effectively inhibited the inflammatory spiral in vitro. Hence, daily soybean intake may be effective for inhibiting chronic inflammation and slowing kidney disease progression.

Prevalence and associations of metabolic syndrome in patients with alcohol use disorder

Excessive alcohol consumption has been associated with different components of the metabolic syndrome (MetS) such as arterial hypertension, dyslipidemia, type 2 diabetes or obesity. We aimed to analyze the prevalence and associations of MetS in patients with Alcohol Use Disorder (AUD). Cross-sectional study in heavy drinkers admitted for the treatment of AUD between 2013 and 2017. Medical comorbidity, anthropometric data, alcohol use and biological parameters were obtained. MetS was established according to the harmonized definition. A total of 728 patients (22% women) were included; median age was 47 years (IQR: 40–53.5), median alcohol consumption was 160 g/day (IQR: 115–240) and prevalence of MetS was 13.9%. The multivariate analysis showed a significant dose–response effect of estimated glomerular filtration (eGFR) and MetS: relative to patients with eGFR > 90 mL/min, those with eGFR (60–90 mL/min) and those with eGFR < 60 mL/min were 1.93 times (95% CI 1.18–3.15) and 5.61 times (95% CI 1.66–19.0) more likely to have MetS, respectively. MetS was significantly associated with hyperuricemia (OR 2.28, 95% CI 1.36–3.82) and elevated serum GGT (OR 3.67, 95% CI 1.80–7.46). Furthermore, for every increase of 1 year in age, the probability of MetS increased significantly (OR 1.03, 95% CI 1.01–1.05). MetS in heavy drinkers is independently associated with reduced kidney function and metabolic risk factors including hyperuricemia and elevated serum GGT.

The association between hypertriglyceridemic-waist phenotype and chronic kidney disease: a cohort study and meta-analysis

Evidence on the association between hypertriglyceridemic-waist phenotype (HTGW) and chronic kidney disease (CKD) is limited and inconsistent. We aimed to explore such association among 7406 Chinese aged ≥ 45 years in a cohort setting, followed by a meta-analysis. Participants were categorized into four phenotypes: NTNW (normal triglycerides and normal waist circumference), NTGW (isolated enlarged waist circumference), HTNW (isolated high triglycerides), and HTGW (high triglycerides and enlarged waist circumference). We used multivariate logistic regression to determine the association between different phenotypes and risk of CKD in the cohort study. For meta-analysis, we searched relevant studies from Embase, Medline, PubMed, and Web of Science from dataset inception up to May 1, 2021. A random-effect model was used to estimate the pooled effect and I² statistic was applied to evaluate heterogeneity. In the cohort study, compared to the NTNW phenotype, HTGW (OR 1.82, 95% CI 1.32 to 2.51, p < 0.01) and NTGW (OR 1.48, 95% CI 1.13 to 1.94, p = 0.004) were significantly associated with CKD risk after 4 years follow-up, but not for the HTNW phenotype. The meta-analysis also showed a positive association between HTGW phenotype and CKD risk (pooled OR 1.53, 95% CI 1.31 to 1.79, I² = 62.4%). Assessment of triglyceridemic-waist phenotypes might help to identify individuals with high-risk of developing CKD.

Chronic Kidney Disease, Metabolic Syndrome and Cardiovascular Risk: Insights and Associated Mechanistic Pathways

Abstract:

This study is a narrative review that aims to address the conceptual, characteristic, pathophysiological, and mechanistic aspects that define the profile of metabolic syndrome and chronic kidney disease. The objective was to investigate current knowledge and elucidate, through discussions on the topic, the main interrelated paths. This review was carried out unsystematically, from March to May 2020, by means of a survey of the literature indexed in the PubMed, Web of Science, and Scopus (Elsevier®) databases. The scientific materials collected showed that the cross-talk between the diseases in question is mainly based on the conditions of resistance to insulin action, endothelial dysfunction, activation pathways of the Renin-Angiotensin-Aldosterone system and adipokine imbalance, also emphasizing the influence of atherosclerotic events in kidney damage. Furthermore, it was reinforced the fact that inflammatory processes play an important role in the worsening and evolution of the clinical condition of patients, especially when they have underlying pathologies chronically treated for subclinical inflammation. It is expected that a greater number of original researches will propose to investigate other possible interactions, with a view to standardized treatment of these diseases or nutritional management.

Association of metabolic syndrome traits with urinary biomarkers in Japanese adults

BACKGROUND

Although metabolic syndrome traits are risk factors for chronic kidney disease, few studies have examined their association with urinary biomarkers.

METHODS

Urinary biomarkers, including A-megalin, C-megalin, podocalyxin, albumin, α₁-microglobulin, β₂-microglobulin, and N-acetyl-β-D-glucosaminidase, were cross-sectionally assessed in 347 individuals (52.7% men) with a urine albumin-to-creatinine ratio (ACR)  < 300 mg/g in a health checkup. Metabolic syndrome traits were adopted from the National Cholesterol Education Program (third revision) of the Adult Treatment Panel criteria modified for Asians.

RESULTS

Participants had a mean body mass index, estimated glomerular filtration rate (eGFR), and median ACR of 23.0 kg/m², 74.8 mL/min/1.73 m², and 7.5 mg/g, respectively. In age- and sex-adjusted logistic regression analysis, A-megalin and albumin were significantly associated with the clustering number of metabolic syndrome traits (3 or more). After further adjustment with eGFR, higher quartiles of A-megalin and albumin were each independently associated with the clustering number of metabolic syndrome traits (adjusted odds ratio for A-megalin: 1.30 per quartile, 95% CI 1.03-1.64; albumin: 1.42 per quartile, 95% CI 1.12-1.79).

CONCLUSIONS

Both urinary A-megalin and albumin are associated with the clustering number of metabolic syndrome traits. Further research on urinary A-megalin is warranted to examine its role as a potential marker of kidney damage from metabolic risk factors.

Metabolic Syndrome Components and Chronic Kidney Disease in a Community Population Aged 40 Years and Older in Southern China: A Cross-Sectional Study

PURPOSE

To investigate the correlation between metabolic syndrome components and chronic kidney disease (CKD) among a community population aged 40 years and older in Southern China.

PATIENTS AND METHODS

From December 2017 to March 2018, 1969 participants (male n = 715, female n = 1254) aged 40 years and older were recruited in Southern China for a cross-sectional survey. A logistic regression model was established to analyze the correlation between metabolic syndrome components and CKD.

RESULTS

Among the 1969 subjects, 407 (20.7%) were CKD patients, including 152 males (prevalence rate 21.3%) and 255 females (prevalence rate 20.3%). Anthropometric data (waist circumference, age, systolic and diastolic blood pressure), serum/plasma data (serum creatinine, serum uric acid, fasting plasma glucose, C-reactive protein, serum triglyceride), urinary and other findings (body mass index, waist-to-hip and waist-to-height ratios, urinary albumin to creatinine ratio, homeostasis model assessment of insulin resistance) were significantly higher in patients with than without CKD (P < 0.05). Metabolic syndrome and at least some of its components were statistically significant risk factors for CKD in models with and without adjustment for diabetes, obesity and hypertension.

CONCLUSION

Metabolic syndrome and its single or combined components are independently associated with CKD in community populations aged 40 years and older. The correlation between some components and CKD remained significant in both non-diabetic and non-obese subjects. Correlations between components of metabolic syndrome and CKD show that it is feasible and necessary to carry out targeted screening and intervention tests in people aged 40 and over.

The Association Between Hypertriglyceridemic-Waist Phenotype and Chronic Kidney Disease in Patients with Type 2 Diabetes: A Cross-Sectional METAL Study

BACKGROUND

The aim of this study was measuring the association between the hypertriglyceridemic-waist (HTGW) phenotype and chronic kidney disease in a large type 2 diabetes population.

METHODS

A total of 4254 diabetic patients from the cross-sectional Environmental Pollutant Exposure and Metabolic Diseases in Shanghai (METAL) study were enrolled. The hypertriglyceridemic-waist (HTGW) phenotype was defined as the presence of an elevated waist circumference (WC) and elevated triglyceride (TG) concentration. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m² or urinary albumin creatinine ratio (uACR) more than 30 mg/g. Linear and multiple logistic regression models were used for measuring the association between HTGW phenotype and chronic kidney disease.

RESULTS

The prevalence of CKD was 29% and 35.8% in total participants and participants with HTGW phenotype, respectively. Subjects in the HTGW phenotype group were more likely to have CKD (OR 1.47, 95% CI: 1.11, 1.95) compared with subjects in the normal waist circumference and normal triglycerides (NTNW) group. HTGW phenotype was both associated with the increasing risk of decreased eGFR (OR 1.31, 95% CI: 1.02, 1.75) and elevated uACR (OR 1.57, 95% CI: 1.18, 2.11). Furthermore, the stratified analysis showed that the strongest positive association between HTGW phenotype and CKD presence was found in the subgroup of presence of hypertension. The associations were all fully adjusted for age, sex, BMI, current smoking, current drinking and other confounding factors.

CONCLUSION

Our study suggested a positive association between the HTGW phenotype and CKD in Chinese type 2 diabetes patients. Further prospective studies are needed to confirm our findings and to investigate the underlying biological mechanisms.

Activation of angiotensin-converting enzyme 2 ameliorates metabolic syndrome-induced renal damage in rats by renal TLR4 and nuclear transcription factor κB downregulation

BACKGROUND

Metabolic syndrome (MetS) is an independent risk factor for chronic kidney disease (CKD) through many mechanisms, including activation of the renin-angiotensin system. The deleterious effects of angiotensin II (Ang II) can be counterbalanced by angiotensin-converting enzyme 2 (ACE2). Diminazene aceturate (DIZE), an anti-trypanosomal drug, can activate ACE2.

OBJECTIVE

This study aimed to investigate the possible reno-protective effects of DIZE in MetS rats with elucidation of related mechanisms.

MATERIALS AND METHODS

Thirty adult male Wistar albino rats were divided equally into control, MetS, and MetS + DIZE groups. Body weight, systolic blood pressure (SBP), and urinary albumin levels were measured. Serum levels of fasting blood glucose (FBG), insulin, uric acid, lipid profile, urea, and creatinine were measured. Homeostasis Model Assessment Index (HOMA-IR) was estimated. Subsequently, renal levels of ACE2, Ang II, malondialdehyde (MDA), reduced glutathione (GSH), and tumor necrosis factor-α (TNF-α) were measured with histopathological and immunohistochemical assessment of TLR4 and NF-κB in renal tissues.

RESULTS

MetS caused dyslipidemia with significant increases in body weight, SBP, FBG, serum insulin, HOMA-IR, uric acid, urea, creatinine, urinary albumin, and renal levels of Ang II, MDA, and TNF-α, whereas renal ACE2 and GSH were significantly decreased. Renal TLR4 and NF-κB immunoreactivity in MetS rats was upregulated. DIZE supplementation of MetS rats induced significant improvements in renal function parameters; this could be explained by the ability of DIZE to activate renal ACE2 and decrease renal Ang II levels with downregulation of renal TLR4 and NF-κB expression.

CONCLUSION

DIZE exerts a reno-protective effect in MetS, mainly by downregulating renal TLR4 and NF-κB levels.

Association between Metabolic Syndrome and Microvascular Complications in Chinese Adults with Type 1 Diabetes Mellitus

BACKGROUND

Both type 1 diabetes mellitus (T1DM) and metabolic syndrome (MetS) are associated with an elevated risk of morbidity and mortality yet with increasing heterogeneity. This study primarily aimed to evaluate the prevalence of MetS among adult patients with T1DM in China and investigate its associated risk factors, and relationship with microvascular complications.

METHODS

We included adult patients who had been enrolled in the Guangdong T1DM Translational Medicine Study conducted from June 2010 to June 2015. MetS was defined according to the updated National Cholesterol Education Program criterion. Logistic regression models were used to estimate the odds ratio (OR) for the association between MetS and the risk of diabetic kidney disease (DKD) and diabetic retinopathy (DR).

RESULTS

Among the 569 eligible patients enrolled, the prevalence of MetS was 15.1%. While female gender, longer diabetes duration, higher body mass index, and glycosylated hemoglobin A1c (HbA1c) were risk factors associated with MetS (OR, 2.86, 1.04, 1.14, and 1.23, respectively), received nutrition therapy education was a protective factor (OR, 0.46). After adjustment for gender, age, diabetes duration, HbA1c, socioeconomic and lifestyle variables, MetS status was associated with an increased risk of DKD and DR (OR, 2.14 and 3.72, respectively; both P<0.05).

CONCLUSION

Although the prevalence of MetS in adult patients with T1DM in China was relatively low, patients with MetS were more likely to have DKD and DR. A comprehensive management including lifestyle modification might reduce their risk of microvascular complications in adults with T1DM.

Comparative Effect of Vitamin D3 and Carbenoxolone Treatments in Metabolic Syndrome Rats

Metabolic syndrome (MetS) is a cluster of cardiovascular risk factors including central obesity, hypertension, insulin resistance, dyslipidemia, and hyperglyemia. MetS is found to be a positive predictor of cardiovascular morbidity and mortality. The present study was planned to test the efficacy of vitamin D3 supplementation as compared to cortisol inhibition on MetS parameters. Wistar rats were allocated into four groups: controls, untreated MetS, and MetS treated with either vitamin D3 (10 μg/kg), or carbenoxolone (50 mg/kg). MetS was induced by combination of high fat diet and oral fructose. After the induction period (8 weeks), MetS was confirmed and treatment modalities started for a further 4 weeks. Compared to untreated MetS, vitamin D3 and carbenoxolone treated rats showed significant reduction in blood pressure, body mass index, lee index, waist circumference, retroperitoneal fat, and improvement of dyslipidemia. Meanwhile, treatment with carbenoxolone significantly lowered the elevated liver enzymes, vitamin D3 resulted in improved insulin sensitivity, enhanced glucose uptake by muscles and replenished glycogen content in the liver and muscles near control levels. In conclusion, although treatment with vitamin D3 or carbenoxolone reduced the risk factors associated with MetS, vitamin D3 was effective in ameliorating insulin resistance which is the hallmark of MetS.

Sex-specific effects of metformin and liraglutide on renal pathology and expression of connexin 45 and pannexin 1 following long-term high-fat high-sugar diet

The comparative effects of the two commonly used antidiabetic drugs metformin and liraglutide on renal pathology and expression of connexin 45 (Cx45) and pannexin 1 (Panx1) in adult obese rats fed high-fat high-sugar diet (HFHSD) were studied. Considering recent data on the profound influence of sex on metformin and liraglutide effects, we compared the effects of both drugs between male and female animals. 44-week-old Sprague-Dawley rats were separated into 4 groups that were fed: standard diet, HFHSD, HFHSD treated with metformin (s.c., 50 mg/kg/day) and HFHSD treated with liraglutide (s.c., 0.3 mg/kg/day). Treatment with metformin or liraglutide lasted for 14 weeks. Histology and immunohistochemistry were performed to quantify renal pathological changes and Cx45 and Panx1 expression. HFHSD caused thickening of the Bowman's capsule (BC). Both metformin and liraglutide failed to ameliorate the BC thickening; metformin even worsened it. Effects on the tubulointerstitial fibrosis score, BC thickness and Cx45 and Panx1 expression were sex-dependent. We found a 50% increase in mitochondria in proximal tubules of metformin- and liraglutide-treated HFHSD-fed rats, but these effects were not dependent on the sex. This is a first study showing that the effects of metformin and liraglutide on kidney pathology in rats fed HFHSD are mostly sex-dependent and that these effects are not necessarily beneficial. Both drugs changed the Cx45 and Panx 1 expression; hence their effects could be related to amelioration of disruptions in intercellular communication.

Association of the metabolic syndrome with mortality and major adverse cardiac events: A large chronic kidney disease cohort

BACKGROUND

Metabolic syndrome with its key components insulin resistance, central obesity, dyslipidaemia, and hypertension is associated with a high risk for cardiovascular events and all-cause mortality in the general population. However, evidence that these findings apply to patients with chronic kidney disease (CKD) with moderately reduced estimated glomerular filtration rate and/or albuminuria is limited.

OBJECTIVES

We aimed to investigate the association between metabolic syndrome and its components with all-cause mortality and cardiovascular outcomes in CKD patients.

METHODS

Prospective observation of a cohort of 5110 CKD patients from the German Chronic Kidney Disease study with 3284 (64.3%) of them having a metabolic syndrome at baseline.

RESULTS

During the follow-up of 6.5 years, 605 patients died and 650 patients experienced major cardiovascular events. After extended data adjustment, patients with a metabolic syndrome had a higher risk for all-cause mortality (hazard ratio [HR] = 1.26, 95% confidence interval [CI]: 1.04-1.54) and cardiovascular events (HR = 1.48, 95% CI: 1.22-1.79). The risk increased steadily with a growing number of metabolic syndrome components (increased waist circumference, glucose, triglycerides, hypertension and decreased HDL cholesterol): HR per component = 1.09 (95% CI: 1.02-1.17) for all-cause mortality and 1.23 (95% CI: 1.15-1.32) for cardiovascular events. This resulted in hazard ratios between 1.50 and 2.50 in the case when four or five components are present. An analysis of individual components of metabolic syndrome showed that the glucose component led to the highest increase in risk for all-cause mortality (HR = 1.68, 95% CI: 1.38-2.03) and cardiovascular events (HR = 1.81, 95% CI: 1.51-2.18), followed by the HDL cholesterol and triglyceride components.

CONCLUSIONS

We observed a high prevalence of metabolic syndrome among patients with moderate CKD. Metabolic syndrome increases the risk for all-cause mortality and cardiovascular events. The glucose and lipid components seem to be the main drivers for the association with outcomes.

Multitarget molecule, PTUPB, to treat diabetic nephropathy in rats

BACKGROUND AND PURPOSE

Diabetic nephropathy is a common complications related to high morbidity and mortality in type 2 diabetes. We investigated the action of the dual modulator, PTUPB, a soluble epoxide hydrolase and cyclooxygenase-2 inhibitor against diabetic nephropathy.

EXPERIMENTAL APPROACH

Sixteen-week-old type 2 diabetic and proteinuric obese ZSF1 rats were treated with vehicle, PTUPB or enalapril for 8 weeks. Measurements were made of epoxyeicosatrienoic acids, thromboxane B2 (TBX2 ) and prostaglandin E2 (PGE2 ) in the kidney of these and lean ZSF1 rats along with their blood pressure.

KEY RESULT

Obese ZSF1 rats were diabetic with fivefold higher fasting blood glucose levels and markedly higher HbA1c levels compared with lean ZSF1 rats. PTUPB nor enalapril reduced fasting blood glucose or HbA1c but alleviated the development of diabetic nephropathy. In PTUPB-treated obese ZSF1 rats, glomerular nephrin expression was preserved. Enalapril also alleviated diabetic nephropathy. Diabetic renal injury in obese ZSF1 rats was accompanied by renal inflammation with six to sevenfold higher urinary MCP-1 (CCR2) level and renal infiltration of CD-68 positive cells. PTUPB and enalapril significantly reduced urinary MCP-1 levels and renal mRNA expression of cytokines. Both PTUPB and enalapril lowered blood pressure. PTUPB but not enalapril decreased hyperlipidaemia and liver injury in obese ZSF1 rats.

CONCLUSION AND IMPLICATIONS

Overall, the dual modulator PTUPB does not treat hyperglycaemia but can effectively alleviate hypertension, diabetic nephropathy, hyperlipidaemia and liver injury in type 2 diabetic rats. Our data further demonstrate that the renal actions of PTUPB are comparable with a current standard diabetic nephropathy treatment.

The Role of Chitosan Oligosaccharide in Metabolic Syndrome: A Review of Possible Mechanisms

Metabolic syndrome, a cluster of metabolic disorders including central obesity, insulin resistance, hyperglycemia, dyslipidemia, and hypertension, has become a major public health problem worldwide. It is of great significance to develop natural products to prevent and treat metabolic syndrome. Chitosan oligosaccharide (COS) is an oligomer of chitosan prepared by the deacetylation of chitin, which is the second most abundant polymer in nature. In recent years, COS has received widespread attention due to its various biological activities. The present review will summarize the evidence from both in vitro and in vivo studies of the beneficial effects of COS on obesity, dyslipidemia, diabetes mellitus, hyperglycemia, and hypertension, and focus attention on possible mechanisms of the prevention and treatment of metabolic syndrome by COS.

Vitamin D3 potentiates the nephroprotective effects of vildagliptin-metformin combination in a rat model of metabolic syndrome

The current study was conducted to investigate the nephroprotective effects of vildagliptin-metformin combination in an experimental model of fructose/salt-induced metabolic syndrome (MetS). A major aim was to evaluate the potential capacity of vitamin D3 to potentiate the pleiotropic nephroprotective effects of vildagliptin-metformin combination. MetS was induced in adult male Wistar rats by adding fructose (10%) to everyday drinking water and salt (3%) to the diet for 6 weeks. Along with the same concentrations of fructose/salt feeding, MetS rats were then treated orally with either vildagliptin (10 mg/kg/day)-metformin (200 mg/kg/day) combination, vitamin D3 (10 μg/kg/day), or the triple therapy for a further 6 weeks. The incidence of MetS was confirmed 6 weeks after fructose/salt consumption, when the rats exhibited significant weight gain, dyslipidemia, hyperuricemia, insulin resistance, hyperinsulinemia, and impaired glucose tolerance. At the end of the 12-week experimental period, MetS rats displayed significantly deteriorated renal function, enhanced intrarenal oxidative stress and inflammation together with exaggerated renal histopathological damages and interstitial fibrosis. The study has corroborated antioxidant, anti-inflammatory, and antifibrotic effects of vildagliptin-metformin combination, vitamin D3, and the triple collaborative therapy, conferring renoprotection in the setting of MetS. Due attention has been paid to the crucial role of dipeptidyl peptidase-4 inhibition and sirtuin-1/5' adenosine monophosphate-activated protein kinase activation as novel therapeutic targets to optimize renoprotection. The apparent potentiating effect, evoked upon coadministration of vitamin D3 with vildagliptin-metformin combination, may provide a cornerstone for further clinical investigations.

NLRP3 Inflammasome in Metabolic-Associated Kidney Diseases: An Update

Metabolic syndrome (MS) is a group of complex metabolic disorders syndrome, which refers to the pathological state of metabolism disorder of protein, fat, carbohydrate and other substances in human body. The kidney is an important organ of metabolism, and various metabolic disorders can lead to the abnormalities in the structure and function of the kidney. The recognition of pathogenesis and treatment measures of renal damage in MS is a very important part for the renal function preserve. Inflammatory response caused by various metabolic factors is a protective mechanism of the body, but persistent inflammation will become a harmful factor and aggravate kidney damage. Inflammasomes are sensors of the innate immune system that play crucial roles in initiating inflammation in response to acute infections and chronic diseases. They are multiprotein complex composed of cytoplasmic sensors (mainly NLR family members), apoptosis-associated speck-like protein (ASC or PYCARD) and pro-caspase-1. After receiving exogenous and endogenous stimuli, the sensors begin to assemble inflammasome and then promote the release of inflammatory cytokines IL-1β and IL-18, resulting in a special way of cell death named pyroptosis. In the kidney, NLRP3 inflammasome can be activated by a variety of pathways, which eventually leads to inflammatory infiltration, renal intrinsic cell damage and renal function decline. This paper reviews the function and specific regulatory mechanism of inflammasome in kidney damage caused by various metabolic disorders, which will provide a new therapeutic perspective and targets for kidney diseases.

Gamma-oryzanol reduces renal inflammation and oxidative stress by modulating AGEs/RAGE axis in animals submitted to high sugar-fat diet

Introduction:

The receptor for AGEs (RAGE) is a multiligand member of the immunoglobulin superfamily of cell surface receptors expressed in many organs, among them, the kidneys. When activated, RAGE leads to a sequence of signaling that results in inflammation and oxidative stress, both involved in kidney disease pathogenesis. Gamma-oryzanol (γOz) comprises a mixture of ferulic acid (FA) esters and phytosterols (sterols and triterpene alcohols) mainly found in rice, with antioxidant and anti-inflammatory activities.

Aim:

To evaluate the effect of γOz to reduce renal inflammation and oxidative stress by modulating AGEs/RAGE axis in animals submitted to a high sugar-fat diet.

Methods:

Male Wistar rats (±187g) were randomly divided into two experimental groups: control (n = 7 animals) and high sugar-fat diet (HSF, n = 14 animals) for 20 weeks. After this period, when the presence of renal disease risk factors was detected in the HSF group (insulin resistance, dyslipidemia, increased systolic blood pressure and obesity), the HSF animals were divided to begin the treatment with γOz or continue receiving only HSF for 10 more weeks.

Results:

No effect of γOz on obesity and metabolic parameters was observed. However, kidney inflammation and oxidative stress decreased as soon as RAGE levels were reduced in HSF + γOz.

Conclusion:

It is possible to conclude that the gamma- oryzanol was effective in reducing inflammation and oxidative stress in the kidney by modulating the AGEs/RAGE axis.