Hypertension and chronic kidney disease

TRPV1 signaling of perirenal adipose tissue promotes DOCA-Salt-induced hypertension and kidney injury

BACKGROUND

Denervation of renal or perirenal adipose tissue (PRAT) can reduce arterial blood pressure in various hypertensive experimental models. Trpv1 (transient receptor potential vanillin 1) channel is highly expressed in the renal sensory nerves and the dorsal root ganglias (DRGs) projected by PRAT. However, it is currently unclear whether Trpv1 in DRGs projected from PRAT can regulate renal hypertension.

METHODS

We used resintoxin (RTX) to block the afferent sensory nerves of rat PRAT. We also constructed Trpv1 -/- mice and Trpv1 +/- mice or used the injection of AAV2-retro-shTrpv1 to detect the effects of Trpv1 knockout or knockdown of PRAT-projected DRGs on deoxycorticosterone acetate (DOCA)-Salt-induced hypertension and kidney injury.

RESULTS

Blocking the afferent sensory nerves of PRAT with RTX can alleviate DOCA-Salt-induced hypertension and renal injury in rats. And this blockade reduces the expression of Trpv1 in the DRGs projected by PRAT. Injecting AAV2-retro-shTrpv1 into the PRAT of DOCA-Salt mice also achieved the same therapeutic effect. However, DOCA-Salt-induced hypertension and renal injury can be treated in Trpv1 +/- mice but not alleviated or even worsened in Trpv1 -/- mice, possibly because of compensatory increase of Trpv5 in DRG of Trpv1 -/- mice.

CONCLUSION

Reducing, rather than eliminating, Trpv1 in DRG from PRAT-projection can reduce blood pressure and kidney damage in DOCA-Salt in rats or mice. Trpv1 in PRAT-DRGs may serve as a therapeutic target for salt-sensitive hypertension and its renal complications.

Association of TyG index with prehypertension or hypertension: a retrospective study in Japanese normoglycemia subjects

Aim

The objective of our study was to investigate the potential association between the triglyceride and glucose (TyG) index and the occurrence of prehypertension or hypertension in a cohort of normoglycemic Japanese subjects.

Methods

The NAGALA physical examination program was conducted in 1994 at Murakami Memorial Hospital in Gifu City, Japan. For our retrospective study, we selected 15,450 participants who had taken part in this program. Our aim was to explore the potential link between the TyG index, a surrogate marker for insulin resistance, and the presence of prehypertension (pre-HTN) or hypertension (HTN). Our analysis included adjustments for clinical demographic attributes and serum biomarkers. Logistic regression was employed to assess the relationship between the TyG index and the likelihood of pre-HTN or HTN.

Results

A total of 15,450 study subjects were included in our analysis. Notably, the prevalence of both pre-HTN and HTN displayed an ascending trend with increasing quartiles of the TyG index. In our comprehensive multivariable logistic regression analysis, when evaluating TyG as a continuous variable, the adjusted odds ratio (OR) for pre-HTN was OR 1.31 [95% CI 1.11-1.56], while for HTN, it was OR 1.76 [95% CI 1.24-2.5] within the fully adjusted model (model 3). When TyG was stratified into quartiles within model 3, the adjusted ORs for pre-HTN were OR 1.16 [95% CI 1.02-1.31], OR 1.22 [95% CI 1.06-1.41], and OR 1.31 [95% CI 1.08-1.59], respectively, using quartile 1 as the reference. The adjusted ORs for HTN in quartiles 2, 3, and 4 were OR 1.22 [95% CI 0.89-1.66], OR 1.4 [95% CI 1.02-1.91], and OR 1.48 [95% CI 1.02-2.15], respectively, within the same model and analysis, with quartile 1 as the reference. Subgroup analysis indicated that the TyG index exhibited a significant positive correlation with the risk of hypertension or prehypertension, except in the subgroup aged ≥65 years.

Conclusion

Our study highlights a robust correlation between the TyG index and the likelihood of pre-HTN or HTN in normoglycemic Japanese subjects. This underscores the potential clinical relevance of the TyG index in refining early hypertension management strategies. Nonetheless, the validation of these findings necessitates larger studies with extended follow-up periods.

Nut Consumption and Effects on Chronic Kidney Disease and Mortality in the United States

Background

Nuts have been found to have beneficial effects on some diseases, including cardiovascular disease and cancer, in several studies. However, there are few studies to show the effects of nuts on chronic kidney disease (CKD). Thus, we conducted this study to examine the association between the consumption frequency of nuts and the prevalence and mortality of CKD among adults in the USA.

Methods

We analyzed data from 6,072 individuals (aged ≥20 years) who participated in the NHANES 2003–2006 following the scheduled procedure. Data on death were provided by the CDC. A logistic regression model was used to evaluate the association between nut consumption frequency and the prevalence of CKD. A Cox proportional hazards regression model was performed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between nut consumption frequency and all-cause mortality and cardiovascular mortality in the CKD and non-CKD populations.

Results

Consuming nuts 1–6 times per week was associated with a lower prevalence of CKD (model 3: OR: 0.67; 95% CI: 0.49–0.91). In addition, higher nut consumption was significantly associated with lower all-cause and cardiovascular mortality in the non-CKD population. For the CKD population, a consistently significant inverse association could be seen between consuming nuts 1–6 per week and all-cause mortality (model 3: HR: 0.63; 95% CI: 0.47–0.86). No groups showed a significant difference in cardiovascular mortality compared with the reference in the full model.

Conclusion

We recommend the CKD population to have an adequate intake of nuts 1–6 times per week, while the consumption frequency can be more flexible for the non-CKD. Further prospective studies should be conducted to confirm this conclusion.

Protective Effect of Coriander (Coriandrum sativum L.) on High-Fructose and High-Salt Diet-Induced Hypertension: Relevant to Improvement of Renal and Intestinal Function

Hypertension has become a leading cardiovascular risk factor worldwide. In this study, we explored the salutary effects and relevant mechanisms of coriander (Coriandrum sativum L.), an herbal plant with culinary and medicinal values, on high-fructose and high-salt diet (HFSD)-induced hypertension in SD rats. Our results showed that oral administration of coriander (1.0 or 2.0 g/kg·bw) effectively attenuated HFSD-induced elevation of systolic blood pressure, diastolic blood pressure, and mean arterial pressure. Coriander also increased the serum levels of vasodilator factors (PGI₂, NO, and eNOS), decreased Na⁺ retention and serum uric acid (UA) level, and ameliorated glucolipid profiles. qPCR results revealed that coriander downregulated the mRNA expression of NHE3, a Na⁺/H⁺ exchanger responsible for Na⁺ absorption, in kidney and small intestine. 16S rDNA sequencing showed that coriander altered the gut microbiota composition with the beneficial bacteria Bifidobacterium and Oscillibacter significantly enriched. Correlation analysis indicated that the abundance of Bifidobacterium was evidently correlated with levels of NHE3, NO, eNOS, and UA. LC-MS/MS analysis revealed that coriander contained a variety of flavonoids including rutin and quercetin. Conclusively, long-term consumption of coriander may ameliorate HFSD-induced hypertension by mitigating HFSD-caused abnormal changes in vascular endothelial function, renal and intestinal sodium absorption, glucolipid homeostasis, and gut microbiota in rats.

Association Between Serum Calcium and the Prevalence of Hypertension Among US Adults

Background: Hypertension is a significant risk factor of cardiovascular diseases, posing a serious threat to global health. Calcium plays an important role in regulating body homeostasis. The association of calcium with hypertension remains uncertain in the general population.

Methods and Results: Cross-sectional data from the 2007–2018 National Health and Nutrition Examination Survey (NHANES) were analyzed. Adjusted multivariable logistic regression analysis and restricted cubic spline were used to investigate the association of serum calcium with the prevalence of hypertension. A total of 26,778 participants were included. The increase in calcium levels showed a positive association with the prevalence of hypertension in all three models with ORs of 1.347 (1.249–1.454), 1.522 (1.401–1.654), and 1.438 (1.306–1.583). The further subgroup analysis demonstrated a robust trend across all categories by sex, age, race, BMI, and eGFR. The restricted cubic spline plot exhibited an S-curve relationship between calcium and hypertension.

Conclusion: Our cross-sectional study demonstrated a positive association between higher serum calcium level and the prevalence of hypertension. Our findings highlighted serum calcium level in hypertensive patients.

Fibroblast growth factor 21 attenuates salt-sensitive hypertension-induced nephropathy through anti-inflammation and anti-oxidation mechanism

BACKGROUND

Patients with salt-sensitive hypertension are often accompanied with severe renal damage and accelerate to end-stage renal disease, which currently lacks effective treatment. Fibroblast growth factor 21 (FGF21) has been shown to suppress nephropathy in both type 1 and type 2 diabetes mice. Here, we aimed to investigate the therapeutic effect of FGF21 in salt-sensitive hypertension-induced nephropathy.

METHODS

Changes of FGF21 expression in deoxycorticosterone acetate (DOCA)-salt-induced hypertensive mice were detected. The influence of FGF21 knockout in mice on DOCA-salt-induced nephropathy were determined. Recombinant human FGF21 (rhFGF21) was intraperitoneally injected into DOCA-salt-induced nephropathy mice, and then the inflammatory factors, oxidative stress levels and kidney injury-related indicators were observed. In vitro, human renal tubular epithelial cells (HK-2) were challenged by palmitate acid (PA) with or without FGF21, and then changes in inflammation and oxidative stress indicators were tested.

RESULTS

We observed significant elevation in circulating levels and renal expression of FGF21 in DOCA-salt-induced hypertensive mice. We found that deletion of FGF21 in mice aggravated DOCA-salt-induced nephropathy. Supplementation with rhFGF21 reversed DOCA-salt-induced kidney injury. Mechanically, rhFGF21 induced AMPK activation in DOCA-salt-treated mice and PA-stimulated HK-2 cells, which inhibited NF-κB-regulated inflammation and Nrf2-mediated oxidative stress and thus, is important for rhFGF21 protection against DOCA-salt-induced nephropathy.

CONCLUSION

These findings indicated that rhFGF21 could be a promising pharmacological strategy for the treatment of salt-sensitive hypertension-induced nephropathy.

Inferior outcomes following cardiac surgery in patients with a functioning renal allograft

OBJECTIVES

Renal transplantation is an effective treatment for end-stage renal failure. The aim of this study was to evaluate outcomes for these patients undergoing cardiac surgery.

METHODS

A retrospective analysis identified patients with a functioning renal allograft at the time of surgery. A 2:1 propensity matching was performed. Patients were matched on: age, sex, left ventricle function, body mass index, preoperative creatinine, operation priority, operation category and logistic EuroSCORE.

RESULTS

Thirty-eight patients undergoing surgery with a functioning renal allograft were identified. The mean age was 62.4 years and 66% were male. A total of 44.7% underwent coronary artery bypass grafting and 26.3% underwent a single valve procedure. The mean logistic EuroSCORE was 10.65. The control population of 76 patients was well matched. Patients undergoing surgery following renal transplantation had a prolonged length of intensive care unit (3.19 vs 1.02 days, P < 0.001) and hospital stay (10.3 vs 7.17 days, P = 0.05). There was a higher in-hospital mortality (15.8% vs 1.3%, P = 0.0027). Longer-term survival on Kaplan-Meier analysis was also inferior (P < 0.001). One-year survival was 78.9% vs 96.1% and 5-year survival was 63.2% vs 90.8%. A further subpopulation of 11 patients with a failed renal allograft was identified and excluded from the main analysis; we report demographic and outcome data for them.

CONCLUSIONS

Patients with a functioning renal allograft are at higher risk of perioperative mortality and inferior long-term survival following cardiac surgery. Patients in this population should be appropriately informed at the time of consent and should be managed cautiously in the perioperative period with the aim of reducing morbidity and mortality.

Association between cardiorespiratory fitness and health care costs in hypertensive men

BACKGROUND AND AIMS

Hypertension increases healthcare costs, but the impact of cardiorespiratory fitness (CRF) on these costs is unknown. This study explored the association between healthcare costs and CRF among hypertensive and normotensive men.

METHODS

We studied 9794 male subjects aged 58.5 ± 11.3 years from the Palo Alto Veterans Affairs Medical Center, including 6413 with and 3381 without hypertension. CRF was classified into four age-stratified categories according to metabolic equivalents (METs) derived from exercise testing: low fit (4.6 ± 1.2 METs; n = 2481), moderate fit (6.6 ± 1.2 METs; n = 2412), fit (8.0 ± 1.3 METs; n = 2505), and high fit (10.8 ± 2.1 METs; n = 2396). Annual costs per subject were quantified over eight years.

RESULTS

Total annual healthcare costs were higher in subjects with hypertension ($34,794, 95% CI, 32,828 to 36,761) in comparison to non-hypertensive subjects ($30,221, 95% CI, 26,104 to 32,450) (p < 0.01). In hypertensive subjects, a graded reduction in annual healthcare costs was observed as CRF was higher; costs were $40,346 for low fit, $35,939 for moderate fit, $32,312 for fit, and $29,277 for high fit subjects (p < 0.001). For each 1-MET increase in CRF, annual costs per subject (USD) were $1752 (95% CI, -2476 to -1,027, p < 0.001) lower among those with hypertension and $1025 (95% CI, -2047 to -2, p < 0.05) lower in those without hypertension.

CONCLUSIONS

Higher CRF is associated with lower healthcare costs in men with and without hypertension. The impact of CRF on healthcare costs is more striking in those with hypertension.

Evaluation of the progression of non-azotemic proteinuric chronic kidney disease in dogs

Proteinuria is a recognized risk factor for progression of canine chronic kidney disease (CKD). However, the prognosis of non-azotemic proteinuric CKD in dogs has been studied only to a limited extent. Moreover, the degree to which proteinuria should be decreased to delay CKD progression remains unknown. The purposes of this study were (1) to identify factors associated with disease progression and (2) to investigate the degree of proteinuria, albuminuria, and blood pressure during the course of treatment associated with the progression using time-averaged urine protein:creatinine ratio (UPC) and urine albumin:creatinine ratio (UAC) in canine non-azotemic proteinuric CKD. Twenty-one dogs with non-azotemic proteinuric CKD were included in the study. High UPC and UAC were associated with CKD progression (P < .05). Time-averaged high UPC and UAC were significantly related to progression (P < .05). The cutoff values of these time-averaged parameters for predicting the progression were 4.1 and 2.0, respectively. In dogs with non-azotemic proteinuric CKD, more severe proteinuria and albuminuria were associated with progression. The present study suggests that because UPC ≥ 4.1 and UAC ≥ 2.0 during treatment were associated with a faster progression of non-azotemic proteinuric CKD, therapeutic intervention is warranted.

Local cyclic adenosine monophosphate signalling cascades-Roles and targets in chronic kidney disease

The molecular mechanisms underlying chronic kidney disease (CKD) are poorly understood and treatment options are limited, a situation underpinning the need for elucidating the causative molecular mechanisms and for identifying innovative treatment options. It is emerging that cyclic 3',5'-adenosine monophosphate (cAMP) signalling occurs in defined cellular compartments within nanometre dimensions in processes whose dysregulation is associated with CKD. cAMP compartmentalization is tightly controlled by a specific set of proteins, including A-kinase anchoring proteins (AKAPs) and phosphodiesterases (PDEs). AKAPs such as AKAP18, AKAP220, AKAP-Lbc and STUB1, and PDE4 coordinate arginine-vasopressin (AVP)-induced water reabsorption by collecting duct principal cells. However, hyperactivation of the AVP system is associated with kidney damage and CKD. Podocyte injury involves aberrant AKAP signalling. cAMP signalling in immune cells can be local and slow the progression of inflammatory processes typical for CKD. A major risk factor of CKD is hypertension. cAMP directs the release of the blood pressure regulator, renin, from juxtaglomerular cells, and plays a role in Na⁺ reabsorption through ENaC, NKCC2 and NCC in the kidney. Mutations in the cAMP hydrolysing PDE3A that cause lowering of cAMP lead to hypertension. Another major risk factor of CKD is diabetes mellitus. AKAP18 and AKAP150 and several PDEs are involved in insulin release. Despite the increasing amount of data, an understanding of functions of compartmentalized cAMP signalling with relevance for CKD is fragmentary. Uncovering functions will improve the understanding of physiological processes and identification of disease-relevant aberrations may guide towards new therapeutic concepts for the treatment of CKD.

Improvement of Vascular Function by Knockdown of Salusin-β in Hypertensive Rats via Nitric Oxide and Reactive Oxygen Species Signaling Pathway

Purpose

Salusin-β, a multifunctional vasoactive peptide, has a potentially important function in the pathological development of hypertension. However, the exact functional role of salusin-β and the underlying mechanism in this process are still not fully understood. The current study aimed to investigate the effects of silencing salusin-β on vascular function and vascular remodeling, as well as its signaling pathways in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY).

Methods

Silencing salusin-β was performed by caudal vein injection of adenovirus expressing salusin-β short hairpin RNA (shRNA). Acetylcholine (ACh)-induced endothelium-dependent relaxation was used to evaluate vasodilator function, and high K⁺ solution-induced constriction was used to evaluate vasoconstriction function.

Results

Salusin-β levels in plasma and its protein expression in mesenteric artery (MA), coronary artery (CA), and pulmonary artery (PA) of SHR were higher than those in WKY. The salusin-β level and expression were decreased effectively by salusin-β shRNA. Knockdown of salusin-β decreased arterial blood pressure (ABP) and high K⁺ solution-induced vascular constrictions, and improved the endothelium-dependent relaxation and vascular remodeling in SHR. The improved effect of silencing salusin-β on ACh-induced relaxation in SHR was almost blocked by the nitric oxide synthase (NOS) inhibitor L-NAME. Compared to WKY, the endothelial NOS (eNOS) activity and level, and nitric oxide (NO) level were decreased, while NAD(P)H oxidase activity and reactive oxygen species (ROS) levels in MA, CA, and PA of SHR were increased, which were all redressed by salusin-β knockdown.

Conclusion

These results indicate that knockdown of salusin-β improves endothelium-dependent vascular relaxation and vascular remodeling and decreases ABP and vasoconstriction in SHR, which might be accomplished by increasing eNOS activation and NO release while inhibiting NAD(P)H oxidase derived-ROS generation. Scavenging salusin-β improves vascular function and then prevents the development and progression of vasculopathy of hypertension.

Development of a prognostic prediction model to estimate the risk of multiple chronic diseases: constructing a copula-based model using Canadian primary care electronic medical record data

Introduction

The ability to estimate risk of multimorbidity will provide valuable information to patients and primary care practitioners in their preventative efforts. Current methods for prognostic prediction modelling are insufficient for the estimation of risk for multiple outcomes, as they do not properly capture the dependence that exists between outcomes.

Objectives

We developed a multivariate prognostic prediction model for the 5-year risk of diabetes, hypertension, and osteoarthritis that quantifies and accounts for the dependence between each disease using a copula-based model.

Methods

We used data from the Canadian Primary Care Sentinel Surveillance Network (CPCSSN) from 2009 onwards, a collection of electronic medical records submitted by participating primary care practitioners across Canada. We identified patients 18 years and older without all three outcome diseases and observed any incident diabetes, osteoarthritis, or hypertension within 5-years, resulting in a large retrospective cohort for model development and internal validation (n=425,228). First, we quantified the dependence between outcomes using unadjusted and adjusted Ø coefficients. We then estimated a copula-based model to quantify the non-linear dependence between outcomes that can be used to derive risk estimates for each outcome, accounting for the observed dependence. Copula-based models are defined by univariate models for each outcome and a dependence function, specified by the parameter θ. Logistic regression was used for the univariate models and the Frank copula was selected as the dependence function.

Results

All outcome pairs demonstrated statistically significant dependence that was reduced after adjusting for covariates. The copula-based model yielded statistically significant θ parameters in agreement with the adjusted and unadjusted Ø coefficients. Our copula-based model can effectively be used to estimate trivariate probabilities.

Discussion

Quantitative estimates of multimorbidity risk inform discussions between patients and their primary care practitioners around prevention in an effort to reduce the incidence of multimorbidity.

Lymphoma survivors have an increased long-term risk of chronic kidney disease

With improving lymphoma survival, late effects of therapy have emerged. Here, we describe pattern of long-term chronic kidney disease (CKD) in lymphoma survivors. Demographics, comorbidities, lymphoma histology, treatment, and outcome were recorded. Glomerular filtration rate (GFR) was recorded at diagnosis, 1, 2, 5, and 10 years. Rate of GFR decline with time and CKD-free survival were recorded. In 397 patients, median age was 55.3 (18-88), 54% were male, 60% were African Americans, 42% had hypertension (HTN), 15% had DM, 13% had hyperuricemia, 86% received chemotherapy, and 14% had baseline CKD. Total 125 (31%) patients developed CKD in 10 years after lymphoma diagnosis. Probability of CKD development increased significantly with time (23% at 1 year to 41% at 10 years). Rate of GFR decline was 4.6 mL/min/per year. Age, HTN, hyperuricemia, and DM (in young patients) predicted risk of CKD. Thus, lymphoma survivors are at substantial long-term risk of CKD development.

A TOR2A Gene Product: Salusin-β Contributes to Attenuated Vasodilatation of Spontaneously Hypertensive Rats

PURPOSE

Attenuated vasodilatation of small arteries is a hallmark feature of hypertension. Salusin-β, which is a TOR2A gene product and an important vasoactive peptide, has a close relationship with cardiovascular disease. This study aimed to determinate the roles of salusin-β in vasodilatation, and its signal pathways in Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR).

METHODS

Isometric tension experiments were performed. Vasodilatation was induced by acetylcholine (ACh) or sodium nitroprusside (SNP).

RESULTS

Plasma salusin-β levels and their protein expressions in coronary artery (CA), mesenteric artery (MA), and pulmonary artery (PA) of SHR were much higher than that of WKY. Intravenous injection of salusin-β increased arterial blood pressure in SHR, while anti-salusin-β IgG decreased it. Salusin-β further deteriorated, while anti-salusin-β IgG improved, the attenuated ACh-induced relaxation, the decreased nitric oxide (NO) level, and endothelial nitric oxide synthase (eNOS) activity in arteries of SHR, and salusin-β had no significant effect on SNP-induced relaxation. The NAD(P)H oxidase activity and reactive oxygen species (ROS) level in arteries of SHR were much higher than that of WKY, which was further increased by salusin-β but reduced by anti-salusin-β IgG. ROS scavenger NAC or antioxidant apocynin significantly inhibited, while SOD inhibitor DETC aggravated, the effects of salusin-β, and the eNOS inhibitor L-NAME inhibited the effects of anti-salusin-β IgG.

CONCLUSIONS

These results indicated that enhanced salusin-β activity is involved in attenuated endothelium-dependent vasodilatation pathogenesis in SHR by activating NAD(P)H oxidase derived ROS generation and inhibiting eNOS activation and NO release.

Epidemiological Characterization of a Directed and Weighted Disease Network Using Data From a Cohort of One Million Patients: Network Analysis

Background

In the past 20 years, various methods have been introduced to construct disease networks. However, established disease networks have not been clinically useful to date because of differences among demographic factors, as well as the temporal order and intensity among disease-disease associations.

Objective

This study sought to investigate the overall patterns of the associations among diseases; network properties, such as clustering, degree, and strength; and the relationship between the structure of disease networks and demographic factors.

Methods

We used National Health Insurance Service-National Sample Cohort (NHIS-NSC) data from the Republic of Korea, which included the time series insurance information of 1 million out of 50 million Korean (approximately 2%) patients obtained between 2002 and 2013. After setting the observation and outcome periods, we selected only 520 common Korean Classification of Disease, sixth revision codes that were the most prevalent diagnoses, making up approximately 80% of the cases, for statistical validity. Using these data, we constructed a directional and weighted temporal network that considered both demographic factors and network properties.

Results

Our disease network contained 294 nodes and 3085 edges, a relative risk value of more than 4, and a false discovery rate-adjusted P value of <.001. Interestingly, our network presented four large clusters. Analysis of the network topology revealed a stronger correlation between in-strength and out-strength than between in-degree and out-degree. Further, the mean age of each disease population was related to the position along the regression line of the out/in-strength plot. Conversely, clustering analysis suggested that our network boasted four large clusters with different sex, age, and disease categories.

Conclusions

We constructed a directional and weighted disease network visualizing demographic factors. Our proposed disease network model is expected to be a valuable tool for use by early clinical researchers seeking to explore the relationships among diseases in the future.

Incidence of Acute Kidney Injury after Adrenalectomy in Patients with Primary Aldosteronism

Background

Aldosterone-induced glomerular hyperfiltration can lead to masked preoperative renal dysfunction in primary aldosteronism(PA) patients. We evaluated whether PA patients had a higher prevalence of acute kidney injury (AKI) after unilateral adrenalectomy. In addition, we identified risk factors for AKI in these subjects.

Methods

This retrospective study included 107 PA patients, and 186 pheochromocytoma patients as a control group, all of whom underwent adrenalectomy between January 2006 and November 2017 at Yonsei University Severance Hospital. The primary outcome was AKI within 48 hours after adrenalectomy. Univariate and multivariate logistic regression analyses were performed to identify predictors of AKI after adrenalectomy.

Results

Overall incidence of AKI was 49/293 (16.7%). In PA patients, the incidence of AKI was 29/107 (27.1%). In contrast, incidence of AKI was 20/186 (10.7%) in pheochromocytoma patients. Univariate and multivariate logistic regression analysis both showed a higher risk of postoperative AKI in PA patients compared to pheochromocytoma patients. In addition, old age, diabetes, longer duration of hypertension, lower preoperative estimated glomerular filtration rate, high aldosterone-cortisol ratio (ACR) and lateralization index (LI) were identified as independent risk factors for postoperative AKI in PA patients after unilateral adrenalectomy.

Conclusion

Incidence and risk of postoperative AKI were significantly higher in PA patients after surgical treatment. High ACR on the tumor side and high LI were associated with higher risk of AKI in PA patients compared to pheochromocytoma patients.

Triglyceride is an independent predictor of type 2 diabetes among middle-aged and older adults: a prospective study with 8-year follow-ups in two cohorts

Background

Although there is abundant evidence indicating the connection between triglyceride and type 2 diabetes mellitus (T2DM), few reports or cohort studies confirm that high TG concentration may predict the incidence of T2DM independently. Thus, we studied the association between triglyceride (TG) and T2DM in a male-dominated, middle and older aged cohort, Tianjin General Hospital Cohort. And we further verified our results in the China Health and Retirement Longitudinal Study (CHARLS).

Methods

We conducted an 8-year retrospective cohort study (2009–2017) with 7241 participants who were free from T2DM at baseline. Three groups were constructed based on baseline TG levels (normal, borderline-high, and high). We used a Cox proportional hazards model to evaluate the relationship between TG and T2DM after adjusting for possible risk factors. A Kaplan–Meier survival analysis was performed to compare the incidence of T2DM among subjects in each TG group. We also tested the association between TG and T2DM in the CHARLS cohort.

Results

In Tianjin General Hospital Cohort, 7241 participants (male 75.8%, female 24.2%) were included, mean age was 61.49 ± 13.85 years at baseline. The cumulative incidence of T2DM in our cohort study was 8.6% (9.2% in men and 6.6% in women). Compared with the normal TG group, the hazard ratios in the borderline and high group were 1.30 (95% CI 1.04–1.62) and 1.54 (95% CI 1.24–1.90). The Kaplan–Meier survival analysis indicated that higher TG levels may predict higher onset of T2DM. These results were verified in the CHARLS cohort, the hazard ratio with T2DM (95% CI) for logTG was 3.94 (2.64–5.87).

Conclusions

Our findings suggest that the TG level may be an independent risk factor and predictor for T2DM.

Current Knowledge of IL-6 Cytokine Family Members in Acute and Chronic Kidney Disease

Healthy kidneys are important for the efficient regulation of metabolism. However, there is an ever increasing population of patients suffering from both acute and chronic kidney diseases that disrupt this homeostasis. This review will explore the emerging roles that interleukin 6 (IL-6) cytokine family members play in the pathogenesis of kidney disease. The IL-6 family of cytokines are involved in a diverse range of physiological functions. In relation to kidney disease, their involvement is no less diverse. Evidence from both preclinical and clinical sources show that IL-6 cytokine family members can play either a deleterious or protective role in response to kidney disease. This appears to be dependent on the type of kidney disease in question or the specific cytokine. Current attempts to use or target IL-6 cytokine family members as therapies of kidney diseases will be highlighted throughout this review. Finally, the involvement of IL-6 cytokine family members in kidney disease will be presented in the context of three regularly overlapping conditions: obesity, hypertension and diabetes.

Hepcidin in chronic kidney disease anemia

Chronic kidney disease (CKD) is associated with several complications that worsen with progression of disease; anemia, disturbances in iron metabolism and inflammation are common features. Inflammatory response starts early, releasing pro-inflammatory cytokines, acute phase reactants and hepcidin. Hepcidin production is modulated by several factors, as hypoxia/anemia, erythropoietin and erythropoiesis products, transferrin saturation (TSAT) and liver iron levels, which are altered in CKD. Treatment of CKD anemia is based on pharmaceutical intervention, with erythropoietic stimulating agents and/or iron supplementation; however, in spite of the erythropoietic benefits, this therapy, on a regular basis, involves risks, namely iron overload. To overcome these risks, some therapeutic approaches are under study to target CKD anemia. Considering the actual alerts about risk of iron overload in dialysis patients, inhibition of hepcidin, the central key player in iron homeostasis, could be a pivotal strategy in the management of CKD anemia.

Blood Pressure and the Risk of Death From Non-cardiovascular Diseases: A Population-based Cohort Study of Korean Adults

Objectives

The objective of this study was to assess the relationship between systolic and diastolic blood pressure (SBP, DBP) and the risk of death from specific causes other than cardiovascular diseases.

Methods

We calculated the risk of specific death by SBP and DBP categories for 506 508 health examinees in 2002-2003 using hazard ratios (HRs) and 95% confidence intervals (CIs) in a Cox proportional hazards model.

Results

Compared to normal levels (SBP <120 or DBP <90 mmHg), stage I systolic and diastolic hypertension (SBP 140-159, DBP 85- 89 mmHg, respectively) were associated with an increased risk of death from diabetes mellitus, alcoholic liver disease, and renal failure (HR, 1.83; 95% CI, 1.51 to 2.22; HR, 1.24; 95% CI, 1.06 to 1.46; HR, 2.30; 95% CI, 1.64 to 3.21; HR, 1.67; 95% CI, 1.27 to 2.20; HR, 1.99; 95% CI, 1.41 to 2.81; HR, 1.31; 95% CI, 0.99 to 1.73, respectively), but a decreased risk of death from intestinal pneumonia (HR, 0.64; 95% CI, 0.42 to 0.98; HR, 0.59; 95% CI, 0.39 to 0.91). Only stage II systolic hypertension (SBP ≥160 mmHg) was associated with an increased risk of death from pneumonia, liver cirrhosis, and intestinal ischemia (HR, 1.54; 95% CI, 1.19 to 1.98; HR, 1.46; 95% CI, 1.00 to 2.15; HR, 3.77; 95% CI, 1.24 to 11.40, respectively), and stage I and II diastolic hypertension (SBP 140-159 and ≥160 mmHg) were associated with an increased risk of death from intestinal ischemia (HR, 3.07; 95% CI, 1.27 to 7.38; HR, 4.39; 95% CI, 1.62 to 11.88, respectively).

Conclusions

An increase in blood pressure levels may alter the risk of death from certain causes other than cardiovascular diseases, a well-known outcome of hypertension, although the mechanism of these associations is not well documented.

American Heart Association High Blood Pressure Protocol 2017: A Literature Review

Hypertension is the most prevalent clinical symptom arising from various cardiovascular disorders. Likewise, it is considered a precursor or sequelae to the development of acute coronary artery disease and congestive heath failure (CHF). Hypertension has been considered a cardinal criterion to determine cardiovascular function. According to the World Health Organization (WHO) global observatory data, hypertension causes more than 7.5 million deaths a year, about 12.8% of the total human mortality. Similarly, the Center for Disease Control (CDC) states that 35% of the American adults have been estimated to have a persistently high blood pressure, which makes it about one in every three adults. Hypertension is a modifiable symptom that can be managed through pharmacological and non-pharmacological methods and standard protocols set forth by the American Heart Association (AHA). With new findings from various clinical trials related to the management of hypertension, new developments and recommendations have been made to update the previously established protocols for hypertension. This article aims to discuss and dissect the modern updates of hypertension management as comprehensively elaborated in the 2017 Hypertension Clinical Practice Guidelines.

Deletion of Nedd4-2 results in progressive kidney disease in mice

NEDD4-2 (NEDD4L), a ubiquitin protein ligase of the Nedd4 family, is a key regulator of cell surface expression and activity of the amiloride-sensitive epithelial Na⁺ channel (ENaC). While hypomorphic alleles of Nedd4-2 in mice show salt-sensitive hypertension, complete knockout results in pulmonary distress and perinatal lethality due to increased cell surface levels of ENaC. We now show that Nedd4-2 deficiency in mice also results in an unexpected progressive kidney injury phenotype associated with elevated ENaC and Na⁺Cl⁻ cotransporter expression, increased Na⁺ reabsorption, hypertension and markedly reduced levels of aldosterone. The observed nephropathy is characterized by fibrosis, tubule epithelial cell apoptosis, dilated/cystic tubules, elevated expression of kidney injury markers and immune cell infiltration, characteristics reminiscent of human chronic kidney disease. Importantly, we demonstrate that the extent of kidney injury can be partially therapeutically ameliorated in mice with nephron-specific deletions of Nedd4-2 by blocking ENaC with amiloride. These results suggest that increased Na⁺ reabsorption via ENaC causes kidney injury and establish a novel role of NEDD4-2 in preventing Na⁺-induced nephropathy. Contrary to some recent reports, our data also indicate that ENaC is the primary in vivo target of NEDD4-2 and that Nedd4-2 deletion is associated with hypertension on a normal Na⁺ diet. These findings provide further insight into the critical function of NEDD4-2 in renal pathophysiology.

The angiotensin-I converting enzyme gene I/D variation contributes to end-stage renal disease risk in Chinese patients with type 2 diabetes receiving hemodialysis

Whether the DD genotype of the angiotensin-I converting enzyme (ACE) I/D variation contributes to end-stage renal disease (ESRD) risk in type 2 diabetes mellitus (T2DM) remains controversial. Differences in study design, case and control definition, sample size and ethnicity may contribute to the discrepancies reported in association studies. We performed a case-control study to evaluate the association of the ACE I/D variation with ESRD risk in Chinese patients with T2DM receiving hemodialysis and analyzed the genotype-phenotype interaction. Unrelated Chinese patients (n = 432) were classified into the non-diabetic nephropathy (DN) control group (n = 222, duration of diabetes >10 years, no signs of renal involvement) and the DN-ESRD group (n = 210; ESRD due to T2DM, receiving hemodialysis). Polymerase chain reaction was used to genotype ACE I/D for all 432 subjects. The frequencies of the ID + DD genotypes were higher in the DN-ESRD group than non-DN control group (65.2 vs. 50.9 %; adjusted OR 1.98 (95 % CI, 1.31-3.00; P = 0.001). In the DN-ESRD group, the DD genotypic subgroup had significantly elevated HbA1c and diastolic blood pressure (DBP) compared to the II subgroup (both P < 0.05). The DD genotype of the ACE I/D variation may be associated with more elevated blood pressure and HbA1c, and therefore may predict the development, progression and severity of DN-ESRD in Chinese patients with T2DM undergoing hemodialysis.

Homocysteine and hydrogen sulfide in epigenetic, metabolic and microbiota related renovascular hypertension

Over the past several years, hydrogen sulfide (H₂S) has been shown to be an important player in a variety of physiological functions, including neuromodulation, vasodilation, oxidant regulation, inflammation, and angiogenesis. H₂S is synthesized primarily through metabolic processes from the amino acid cysteine and homocysteine in various organ systems including neuronal, cardiovascular, gastrointestinal, and kidney. Derangement of cysteine and homocysteine metabolism and clearance, particularly in the renal vasculature, leads to H₂S biosynthesis deregulation causing or contributing to existing high blood pressure. While a variety of environmental influences, such as diet can have an effect on H₂S regulation and function, genetic factors, and more recently epigenetics, also have a vital role in H₂S regulation and function, and therefore disease initiation and progression. In addition, new research into the role of gut microbiota in the development of hypertension has highlighted the need to further explore these microorganisms and how they influence the levels of H₂S throughout the body and possibly exploiting microbiota for use of hypertension treatment. In this review, we summarize recent advances in the field of hypertension research emphasizing renal contribution and how H₂S physiology can be exploited as a possible therapeutic strategy to ameliorate kidney dysfunction as well as to control blood pressure.

Transient renal impairment in the absence of pre-existing chronic kidney disease in patients with unilateral ureteric stone impaction

This study aims to describe the rate and characteristics of transient renal impairment in unilateral ureteric stone patients without chronic kidney disease (CKD) and to identify factors that may have influenced renal function of these patients. Unilateral ureteric stone patients who visited our hospital's emergency department from December, 2009 to December, 2015 were divided into two groups based on estimated glomerular filtration rate (eGFR): group I (patients with eGFR ≥ 60 ml/min/1.73 m²) and group II (eGFR < 60 ml/min/1.73 m²). A univariate comparison between groups I and II was performed. Multivariable logistic regression analysis was performed to determine factors that influenced renal function. There were 107 patients in group II, which constituted 5.6 % of the total patients. In the multivariable logistic regression analysis, age (p < 0.001, odds ratio [OR] = 1.069, confidence interval [CI] = 1.049-1.089), hypertension (p < 0.001, OR = 2.302, CI = 1.467-3.611), stone size (p = 0.001, OR = 1.141, CI = 1.057-1.231), white blood cell count (p = 0.001, OR = 1.132, CI = 1.055-1.215) and hematuria (p < 0.001, OR = 0.383, CI = 0.231-0.636) were found to be independent factors for renal impairment. Based on the results of this study, the rate of renal impairment was 6 % of the unilateral ureteric stone patients without pre-existing CKD. Age and hypertension were found to be independent factors for renal impairment; NSAIDs should be used cautiously or other agents for pain relief such as opioids should be considered in old aged patients with hypertension.

The cytoskeleton as a novel target for treatment of renal fibrosis

The incidence of chronic kidney disease (CKD) is increasing, with an estimated prevalence of 12% in the United States (Synder et al., 2009). While CKD may progress to end-stage renal disease (ESRD), which necessitates renal replacement therapy, i.e. dialysis or transplantation, most CKD patients never reach ESRD due to the increased risk of death from cardiovascular disease. It is well-established that regardless of the initiating insult - most often diabetes or hypertension - fibrosis is the common pathogenic pathway that leads to progressive injury and organ dysfunction (Eddy, 2014; Duffield, 2014). As such, there has been extensive research into the molecular and cellular mechanisms of renal fibrosis; however, translation to effective therapeutic strategies has been limited. While a role for the disruption of the cytoskeleton, most notably the actin network, has been established in acute kidney injury over the past two decades, a role in regulating renal fibrosis and CKD is only recently emerging. This review will focus on the role of the cytoskeleton in regulating pro-fibrotic pathways in the kidney, as well as data suggesting that these pathways represent novel therapeutic targets to manage fibrosis and ultimately CKD.

Association Between Change in Serum Aminotransferase and Mortality: A Nationwide Cohort Study in Korea

There is little information on how the change in serum aminotransferase affects mortality. We investigated the association between changes in serum aminotransferase levels and mortality from all causes, cardiovascular disease (CVD), and liver disease.Three percent of men from the Korean National Health Insurance database were sampled randomly at the end of 2002. After excluding patients with cancer, CVD, CVD risk factors, or liver disease, those who participated in 2 consecutive rounds of the national health screening examination were included (n = 68,431). The primary outcome was CVD mortality. Secondary outcomes were liver disease mortality and all-cause mortality. Change in metabolic profiles was analyzed based on changes in liver enzyme levels. Elevated levels of serum aminotransferase were associated with CVD, liver disease, and all-cause mortality. Men who had sustained elevation of serum aminotransferase during 2 subsequent liver enzyme tests showed a significantly higher risk of CVD mortality (adjusted hazard ratio [aHR] 1.95; 95% confidence interval [CI] 1.07-3.56, 2.29; 1.27-4.12) than the sustained normal group. In contrast, the normalization group (aHR 1.52, 95% CI 0.82-2.81 for aspartate aminotransferase [AST]; aHR 1.35, 95% CI 0.70-2.61 for alanine aminotransferase [ALT]) and the new elevation group (aHR 1.27, 0.66-2.44 for AST; aHR 0.99, 95% CI 0.49-2.20 for ALT) were not different from the sustained normal group in CVD mortality.Individuals with serum aminotransferase elevation, particularly when sustained, are at higher risk of mortality, and should receive appropriate medical attention.

Renal risk-benefit determinants of recombinant human erythropoietin therapy in the remnant kidney rat model - hypertension, anaemia, inflammation and drug dose

Clinical studies showed that high doses of recombinant human erythropoietin (rHuEPO) used to correct anaemia in chronic kidney disease (CKD) hyporesponsive patients may lead to deleterious effects. The aim of this study was to analyze the effects of rHuEPO in doses usually used to correct CKD-anaemia (100, 200 IU/kg body weight (BW) per week) and in higher doses used in the treatment of hyporesponsive patients (400, 600 IU/kg BW per week), focusing on renal damage, hypoxia, inflammation and fibrosis. Male Wistar rats with chronic renal failure (CRF) induced by 5/6 nephrectomy were treated with rHuEPO or with vehicle, over a 3-week period. Haematological, biochemical and renal function analyses were performed. Kidney and liver mRNA levels were evaluated by quantitative real-time polymerase chain reaction (qPCR) and protein expression by Western blot and immunohistochemistry. Kidney histopathological evaluations were also performed. The CRF group developed anaemia, hypertension and a high score of renal histopathologic lesions. Correction of anaemia was achieved with all rHuEPO doses, with improvement in hypertension, renal function and renal lesions. In addition, the higher rHuEPO doses also improved inflammation. Blood pressure was reduced in all rHuEPO-treated groups, compared to the CRF group, but increased in a dose-dependent manner. The current study showed that rHuEPO treatment corrected anaemia and improved urinary albumin excretion, particularly at lower doses. In addition, it is suggested that a short-term treatment with high doses, used to overcome an episode of hyporesponsiveness to rHuEPO therapy, can present benefits by reducing inflammation, without worsening of renal lesions; however, the pro-hypertensive effect should be considered, and carefully managed to avoid a negative cardiorenal impact.