Why do young people with chronic kidney disease die early?

Differential Myocardial Responses in Male and Female Rats with Uremic Cardiomyopathy

Uremic cardiomyopathy, characterized by diastolic dysfunction, left ventricular hypertrophy (LVH), and fibrosis, is a common cardiovascular complication of chronic kidney disease (CKD). Men are at a higher risk for cardiovascular and renal diseases, compared to age-matched, pre-menopausal women. We aimed to investigate the influence of sex on the severity of uremic cardiomyopathy through the characterization of functional and molecular indices of myocardial remodeling in a rat model. CKD was induced by a 5/6 nephrectomy in 9-week-old male and female Wistar rats. Serum and urine tests, transthoracic echocardiography, left ventricular (LV) histology, and quantitative reverse transcription polymerase chain reaction (RT-qPCR) were performed at week 8 or 9. Moreover, LV alterations were also tested in permeabilized cardiomyocytes (CMs) by force measurements and Western immunoblotting. CKD resulted in the development of a more severe uremic cardiomyopathy in male rats-including LVH, LV diastolic dysfunction, and fibrosis-than in female rats, where only LVH was observed. A uremic cardiomyopathy was also associated with a decrease in maximal Ca2+-activated force (Fmax) in CMs of male rats. Additionally, increases in CM Ca2+-independent passive stiffness (Fpassive) and decreases in cardiac myosin-binding protein C (cMyBP-C) phosphorylation levels were significantly larger in male than female rats. In conclusion, a uremic cardiomyopathy involved cardiac remodeling in both sexes. Nevertheless, male rats exhibited more pronounced signs of macroscopic and microscopic alterations than their female counterparts, illustrating a sex-dependent component of uremic cardiomyopathy.

Young-onset chronic kidney disease in Mexico: Secondary analysis of global burden of disease study, 1990-2019

OBJECTIVE

To report the burden of young-onset chronic kidney disease (CKD) in Mexico from 1990 to 2019, and to assess the association between young-onset CKD burden with the Socio-Demographic Index (SDI), and the Healthcare Access and Quality Index (HAQ).

METHODS

Secondary analysis of data using the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) by sex, age groups, states, and subcauses. Mortality, years of life lost (YLL), years lived with disability (YLD), and disability-adjusted life years (DALY), were obtained.

RESULTS

Between 1990 and 2019, the young-onset CKD mortality rate increased by 87.3% (126.3% for men and 48.1% for women). In 2019, this rate was highest in Tlaxcala, Estado de México, Puebla, Veracruz, Jalisco, and Guanajuato (all above 8 deaths per 100,000 inhabitants); Sinaloa and Quintana Roo had the lowest mortality rates (under 3.5 deaths per 100,000 inhabitants). While men had a higher rate of YLL, women were more likely to present YLD due to CKD. In 1990 there was a negative and statistically significant correlation between the HAQ Index and the young-onset CKD DALY rate.

CONCLUSIONS

In the last 30 years, the burden of early-onset chronic CKD has had an unprecedented increase among the Mexican population, compromising the fulfillment of the Sustainable Development Goals. This will be unattainable if actions to promote healthy lifestyles and prevent kidney disease are not immediately established and articulated, starting with the youngest age groups.

The protective effect of Bergamot Polyphenolic Fraction on reno-cardiac damage induced by DOCA-salt and unilateral renal artery ligation in rats

To date, the complex pathological interactions between renal and cardiovascular systems represent a real global epidemic in both developed and developing countries. In this context, renovascular hypertension (RVH) remains among the most prevalent, but also potentially reversible, risk factor for numerous reno-cardiac diseases in humans and pets. Here, we investigated the anti-inflammatory and reno-cardiac protective effects of a polyphenol-rich fraction of bergamot (BPF) in an experimental model of hypertension induced by unilateral renal artery ligation. Adult male Wistar rats underwent unilateral renal artery ligation and treatment with deoxycorticosterone acetate (DOCA) (20 mg/kg, s.c.), twice a week for a period of 4 weeks, and 1% sodium chloride (NaCl) water (n = 10). A subgroup of hypertensive rats received BPF (100 mg/kg/day for 28 consecutive days, n = 10) by gavage. Another group of animals was treated with a sub-cutaneous injection of vehicle (that served as control, n = 8). Unilateral renal artery ligation followed by treatment with DOCA and 1% NaCl water resulted in a significant increase in mean arterial blood pressure (MAP; p< 0.05. vs CTRL) which strongly increased the resistive index (RI; p<0.05 vs CTRL) of contralateral renal artery flow and kidney volume after 4 weeks (p<0.001 vs CTRL). Renal dysfunction also led to a dysfunction of cardiac tissue strain associated with overt dyssynchrony in cardiac wall motion when compared to CTRL group, as shown by the increased time-to-peak (T2P; p<0.05) and the decreased whole peak capacity (Pk; p<0.01) in displacement and strain rate (p<0.05, respectively) in longitudinal motion. Consequently, the hearts of RAL DOCA-Salt rats showed a larger time delay between the fastest and the lowest region (Maximum Opposite Wall Delay-MOWD) when compared to CTRL group (p<0.05 in displacement and p <0.01 in strain rate). Furthermore, a significant increase in the levels of the circulating pro-inflammatory cytokines and chemokines (p< 0.05 for IL-12(40), p< 0.01 for GM-CSF, KC, IL-13, and TNF- α) and in the NGAL expression of the ligated kidney (p< 0.001) was observed compared to CTRL group. Interestingly, this pathological condition is prevented by BPF treatment. In particular, BPF treatment prevents the increase of blood pressure in RAL DOCA-Salt rats (p< 0.05) and exerts a protective effect on the volume of the contralateral kidney (p <0.01). Moreover, BPF ameliorates cardiac tissue strain dysfunction by increasing Pk in displacement (p <0.01) and reducing the T2P in strain rate motion (p<0.05). These latter effects significantly improve MOWD (p <0.05) preventing the overt dyssynchrony in cardiac wall motion. Finally, the reno-cardiac protective effect of BPF was associated with a significant reduction in serum level of some pro-inflammatory cytokines and chemokines (p<0.05 for KC and IL-12(40), p<0.01 for GM-CSF, IL-13, and TNF- α) restoring physiological levels of renal neutrophil gelatinase-associated lipocalin (NGAL, p<0.05) protein of the tethered kidney. In conclusion, the present results show, for the first time, that BPF promotes an efficient renovascular protection preventing the progression of inflammation and reno-cardiac damage. Overall, these data point to a potential clinical and veterinary role of dietary supplementation with the polyphenol-rich fraction of citrus bergamot in counteracting hypertension-induced reno-cardiac syndrome.

Mitochondrial Impairment: A Link for Inflammatory Responses Activation in the Cardiorenal Syndrome Type 4

Cardiorenal syndrome type 4 (CRS type 4) occurs when chronic kidney disease (CKD) leads to cardiovascular damage, resulting in high morbidity and mortality rates. Mitochondria, vital organelles responsible for essential cellular functions, can become dysfunctional in CKD. This dysfunction can trigger inflammatory responses in distant organs by releasing Damage-associated molecular patterns (DAMPs). These DAMPs are recognized by immune receptors within cells, including Toll-like receptors (TLR) like TLR2, TLR4, and TLR9, the nucleotide-binding domain, leucine-rich-containing family pyrin domain-containing-3 (NLRP3) inflammasome, and the cyclic guanosine monophosphate (cGMP)-adenosine monophosphate (AMP) synthase (cGAS)-stimulator of interferon genes (cGAS-STING) pathway. Activation of these immune receptors leads to the increased expression of cytokines and chemokines. Excessive chemokine stimulation results in the recruitment of inflammatory cells into tissues, causing chronic damage. Experimental studies have demonstrated that chemokines are upregulated in the heart during CKD, contributing to CRS type 4. Conversely, chemokine inhibitors have been shown to reduce chronic inflammation and prevent cardiorenal impairment. However, the molecular connection between mitochondrial DAMPs and inflammatory pathways responsible for chemokine overactivation in CRS type 4 has not been explored. In this review, we delve into mechanistic insights and discuss how various mitochondrial DAMPs released by the kidney during CKD can activate TLRs, NLRP3, and cGAS-STING immune pathways in the heart. This activation leads to the upregulation of chemokines, ultimately culminating in the establishment of CRS type 4. Furthermore, we propose using chemokine inhibitors as potential strategies for preventing CRS type 4.

Alterations of HDL's to piHDL's Proteome in Patients with Chronic Inflammatory Diseases, and HDL-Targeted Therapies

Chronic inflammatory diseases, such as rheumatoid arthritis, steatohepatitis, periodontitis, chronic kidney disease, and others are associated with an increased risk of atherosclerotic cardiovascular disease, which persists even after accounting for traditional cardiac risk factors. The common factor linking these diseases to accelerated atherosclerosis is chronic systemic low-grade inflammation triggering changes in lipoprotein structure and metabolism. HDL, an independent marker of cardiovascular risk, is a lipoprotein particle with numerous important anti-atherogenic properties. Besides the essential role in reverse cholesterol transport, HDL possesses antioxidative, anti-inflammatory, antiapoptotic, and antithrombotic properties. Inflammation and inflammation-associated pathologies can cause modifications in HDL's proteome and lipidome, transforming HDL from atheroprotective into a pro-atherosclerotic lipoprotein. Therefore, a simple increase in HDL concentration in patients with inflammatory diseases has not led to the desired anti-atherogenic outcome. In this review, the functions of individual protein components of HDL, rendering them either anti-inflammatory or pro-inflammatory are described in detail. Alterations of HDL proteome (such as replacing atheroprotective proteins by pro-inflammatory proteins, or posttranslational modifications) in patients with chronic inflammatory diseases and their impact on cardiovascular health are discussed. Finally, molecular, and clinical aspects of HDL-targeted therapies, including those used in therapeutical practice, drugs in clinical trials, and experimental drugs are comprehensively summarised.

Renal and Urological Disorders Associated With Inflammatory Bowel Disease

Renal and urinary tract complications related to inflammatory bowel disease (IBD) have been relatively understudied in the literature compared with other extraintestinal manifestations. Presentation of these renal manifestations can be subtle, and their detection is complicated by a lack of clarity regarding the optimal screening and routine monitoring of renal function in IBD patients. Urolithiasis is the most common manifestation. Penetrating Crohn's disease involving the genitourinary system as an extraintestinal complication is rare but associated with considerable morbidity. Some biologic agents used to treat IBD have been implicated in progressive renal impairment, although differentiating between drug-related side effects and deteriorating kidney function due to extraintestinal manifestations can be challenging. The most common findings on renal biopsy of IBD patients with renal injury are tubulointerstitial nephritis and IgA nephropathy, the former also being associated with drug-induced nephrotoxicity related to IBD medication. Amyloidosis, albeit rare, must be diagnosed early to reduce the chance of progression to renal failure. In this review, we evaluate the key literature relating to renal and urological involvement in IBD and emphasize the high index of suspicion required for the prompt diagnosis and treatment of these manifestations and complications, considering the potential severity and implications of acute or chronic loss of renal function. We also provide suggestions for future research priorities.

Glomerular filtration rate as a kidney outcome of diabetic kidney disease: a focus on new antidiabetic drugs

Diabetes has reached epidemic proportions, both in Korea and worldwide and is associated with an increased risk of chronic kidney disease and kidney failure (KF). The natural course of kidney function among people with diabetes (especially type 2 diabetes) may be complex in real-world situations. Strong evidence from observational data and clinical trials has demonstrated a consistent association between decreased estimated glomerular filtration rate (eGFR) and subsequent development of hard renal endpoints (such as KF or renal death). The disadvantage of hard renal endpoints is that they require a long follow-up duration. In addition, there are many patients with diabetes whose renal function declines without the appearance of albuminuria, measurement of the eGFR is emphasized. Many studies have used GFR-related parameters, such as its change, decline, or slope, as clinical endpoints for kidney disease progression. In this respect, understanding the trends in GFR changes could be crucial for developing clinical management strategies for the prevention of diabetic complications. This review focuses on the clinical implication of the eGFR-related parameters that have been used so far in diabetic kidney disease. We also discuss the use of recently developed new antidiabetic drugs for kidney protection, with a focus on the GFR as clinical endpoints.

A Consistency Model for Identifying the Effects of n-3 and n-6 Fatty Acids on Lipoproteins in Dialysis Patients

Numerous randomized controlled trials (RCTs) and meta-analyses have assessed the effects of supplemental dietary polyunsaturated fatty acids (PUFAs) on levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) and the LDL/HDL ratio in patients receiving renal replacement therapy (RRT). However, results are ambiguous due to mixed reports of various nutrients used in the intervention group. We performed a network meta-analysis of RCTs to assess the effects of PUFAs on lipid profiles in patients undergoing RRT. RCTs performed before November 2021 were gathered from three databases. The means, standard deviations and the number of cases for each arm were independently extracted by two authors to form a network meta-analysis of LDL and HDL levels and the LDL/HDL ratio in a random effects model. Twenty-eight RCTs (n = 2017 subjects) were included in this study. The pooled results revealed that the combination of omega-3 fatty acids (n-3) and omega-6 fatty acids (n-6) produced significantly lower LDL (standardized mean difference (SMD) = −1.43, 95% confidence interval: −2.28 to −0.57) than the placebo. Both n-3 fatty acids (SMD = 0.78) and the combination of n-3 + n-6 (SMD = 1.09) benefited HDL significantly compared with placebo. Moreover, n-3 alone also exhibited a significantly lower LDL/HDL ratio than placebo. Collectively, PUFAs seem to be adequate nutrients for controlling lipoproteins in patients undergoing RRT. Specifically, n-3 + n-6 supplementation improved LDL levels, while n-3 improved HDL levels and the LDL/HDL ratio. However, our data provide limited information on specific dosages of PUFAs to form a concrete recommendation.

Prognosis and risk factors for cardiac valve calcification in Chinese end-stage kidney disease patients on combination therapy with hemodialysis and hemodiafiltration

BACKGROUND

Cardiac valve calcification (CVC) is an important risk factor for cardiovascular complications. However, limited data are available concerning the prevalence, clinical features and risk factors for CVC in end-stage kidney disease (ESKD) patients. In this study, we aimed to assess these parameters in Chinese ESKD patients receiving combination therapy with hemodialysis and hemodiafiltration.

METHODS

We conducted a cross-sectional study on 293 ESKD patients undergoing combination therapy of hemodialysis and hemodiafiltration at the First Affiliated Hospital of Chongqing Medical University from October 2014 to December 2015. CVC was evaluated via echocardiography.

RESULTS

ESKD patients with CVC had a higher prevalence of diabetes mellitus, aortic and/or coronary artery calcification, arrhythmia, heart failure and coronary heart disease; increased systolic, diastolic and pulse pressure; longer duration of hemodialysis and hypertension; reduced hemoglobin, albumin and high-density lipoprotein cholesterol levels; and increased serum calcium and calcium-phosphorus product levels compared with those without CVC. Logistic regression analysis showed that increased dialysis duration (p = 0.006, OR = 2.25), serum calcium levels (p = 0.046, OR = 2.04) and pulse pressure (p < 0.001, OR = 3.22), the presence of diabetes (p = 0.037, OR = 1.81) and decreased serum albumin levels (p = 0.047, OR = 0.54) were risk factors for CVC. The correlation analysis indicated a significantly increased CVCs prevalence with an increase prevalence of heart failure, aortic and coronary artery calcification.

CONCLUSIONS

CVC represents a common complication and a danger signal for cardiovascular events in ESKD patients undergoing combination therapy of hemodialysis and hemodiafiltration. The presence of diabetes, increased pulse pressure, long dialysis duration, hypoalbuminemia and high serum calcium levels were independent risk factors for CVC.

Ischemic preconditioning protects the heart against ischemia-reperfusion injury in chronic kidney disease in both males and females

BACKGROUND

Uremic cardiomyopathy is a common cardiovascular complication of chronic kidney disease (CKD) characterized by left ventricular hypertrophy (LVH) and fibrosis enhancing the susceptibility of the heart to acute myocardial infarction. In the early stages of CKD, approximately 60% of patients are women. We aimed to investigate the influence of sex on the severity of uremic cardiomyopathy and the infarct size-limiting effect of ischemic preconditioning (IPRE) in experimental CKD.

METHODS

CKD was induced by 5/6 nephrectomy in 9-week-old male and female Wistar rats. Two months later, serum and urine laboratory parameters were measured to verify the development of CKD. Transthoracic echocardiography was performed to assess cardiac function and morphology. Cardiomyocyte hypertrophy and fibrosis were measured by histology. Left ventricular expression of A- and B-type natriuretic peptides (ANP and BNP) were measured by qRT-PCR and circulating BNP level was measured by ELISA. In a subgroup of animals, hearts were perfused according to Langendorff and were subjected to 35 min global ischemia and 120 min reperfusion with or without IPRE (3 × 5 min I/R cycles applied before index ischemia). Then infarct size or phosphorylated and total forms of proteins related to the cardioprotective RISK (AKT, ERK1,2) and SAFE (STAT3) pathways were measured by Western blot.

RESULTS

The severity of CKD was similar in males and females. However, CKD males developed more severe LVH compared to females as assessed by echocardiography. Histology revealed cardiac fibrosis only in males in CKD. LV ANP expression was significantly increased due to CKD in both sexes, however, LV BNP and circulating BNP levels failed to significantly increase in CKD. In both sexes, IPRE significantly decreased the infarct size in both the sham-operated and CKD groups. IPRE significantly increased the phospho-STAT3/STAT3 ratio in sham-operated but not in CKD animals in both sexes. There were no significant differences in phospho-AKT/AKT and phospho-ERK1,2/ERK1,2 ratios between the groups.

CONCLUSION

The infarct size-limiting effect of IPRE was preserved in both sexes in CKD despite the more severe uremic cardiomyopathy in male CKD rats. Further research is needed to identify crucial molecular mechanisms in the cardioprotective effect of IPRE in CKD.

Comparison of the antiremodeling effects of losartan and mirabegron in a rat model of uremic cardiomyopathy

Uremic cardiomyopathy is characterized by diastolic dysfunction (DD), left ventricular hypertrophy (LVH), and fibrosis. Angiotensin-II plays a major role in the development of uremic cardiomyopathy via nitro-oxidative and inflammatory mechanisms. In heart failure, the beta-3 adrenergic receptor (β3-AR) is up-regulated and coupled to endothelial nitric oxide synthase (eNOS)-mediated pathways, exerting antiremodeling effects. We aimed to compare the antiremodeling effects of the angiotensin-II receptor blocker losartan and the β3-AR agonist mirabegron in uremic cardiomyopathy. Chronic kidney disease (CKD) was induced by 5/6th nephrectomy in male Wistar rats. Five weeks later, rats were randomized into four groups: (1) sham-operated, (2) CKD, (3) losartan-treated (10 mg/kg/day) CKD, and (4) mirabegron-treated (10 mg/kg/day) CKD groups. At week 13, echocardiographic, histologic, laboratory, qRT-PCR, and Western blot measurements proved the development of uremic cardiomyopathy with DD, LVH, fibrosis, inflammation, and reduced eNOS levels, which were significantly ameliorated by losartan. However, mirabegron showed a tendency to decrease DD and fibrosis; but eNOS expression remained reduced. In uremic cardiomyopathy, β3-AR, sarcoplasmic reticulum ATPase (SERCA), and phospholamban levels did not change irrespective of treatments. Mirabegron reduced the angiotensin-II receptor 1 expression in uremic cardiomyopathy that might explain its mild antiremodeling effects despite the unchanged expression of the β3-AR.

Endogenous estrogen exposure and chronic kidney disease; a 15-year prospective cohort study

BACKGROUND

Despite strong evidence demonstrating the role of estrogen as a protective factor for kidney function in women, limited data are available regarding the influence of endogenous estrogen exposure (EEE) on chronic kidney disease (CKD). The present study aimed to assess the incidence of CKD in women with various levels of EEE.

METHODS

In a prospective population-based study over a 15-year follow-up, a total of 3043 eligible women aged 30-70 years, participating in Tehran-Lipid and Glucose-Study were recruited and divided into two groups (EEE < 11 and EEE ≥ 11 years). EEE calculated based on age at menarche, age at menopause, number and duration of pregnancies, lactation, and duration of oral contraceptive use after excluding the progesterone dominant phase of the menstrual cycle. Cox's proportional hazards model was applied to estimate the hazard ratio of CKD between the study groups, after adjusting for confounders.

RESULTS

The total cumulative incidence rate of CKD was 50.1 per 1000 person years; 95% CI: 47.7-52.6); this was 53.9 (95%CI, 50.2-57.8) and 47.1 (95%CI, 44.0-50.4) per 1000 person years in women with EEE < 11 and EEE ≥ 11 years, respectively. The model adjusted for age, BMI, smoking, hypertension, and diabetes showed that the hazard ratio (HR) of incidence CKD in women with EEE < 11 compare to those with EEE ≥ 11 years in the subgroup of women aged< 45 years was 2.66(95% CI, 2.2, 3.2), whereas, in the subgroup aged ≥45 years, it was 1.22 (95% CI, 1.04, 1.4).

CONCLUSION

This study shows a higher HR of CKD incidence in women with low EEE levels in their later life. Screening of these women for CKD may be recommended.

Early inflammatory changes and CC chemokine ligand-8 upregulation in the heart contribute to uremic cardiomyopathy

Uremic cardiomyopathy is a common complication in chronic kidney disease (CKD) patients, accounting for a high mortality rate. Several mechanisms have been proposed to link CKD and cardiac alterations; however, the early cardiac modifications that occur in CKD that may trigger cardiac remodeling and dysfunction remain largely unexplored. Here, in a mouse model of CKD induced by 5/6 nephrectomy, we first analyzed the early transcriptional and inflammatory changes that occur in the heart. Five days after 5/6 nephrectomy, RNA-sequencing showed the upregulation of 54 genes in the cardiac tissue of CKD mice and the enrichment of biological processes related to immune system processes. Increased cardiac infiltration of T-CD4⁺ lymphocytes, myeloid cells, and macrophages during early CKD was observed. Next, since CC chemokine ligand-8 (CCL8) was one of the most upregulated genes in the heart of mice with early CKD, we investigated the effect of acute and transient CCL8 inhibition on uremic cardiomyopathy severity. An increase in CCL8 protein levels was confirmed in the heart of early CKD mice. CCL8 inhibition attenuated the early infiltration of T-CD4⁺ lymphocytes and macrophages to the cardiac tissue, leading to a protection against chronic cardiac fibrotic remodeling, inflammation and cardiac dysfunction induced by CKD. Altogether, our data show the occurrence of transcriptional and inflammatory changes in the heart during the early phases of CKD and identify CCL8 as a key contributor to the early cardiac inflammatory state that triggers further cardiac remodeling and dysfunction in uremic cardiomyopathy.

Whole-Mount Kidney Clearing and Visualization Reveal Renal Sympathetic Hyperinnervation in Heart Failure Mice

Developing a three-dimensional (3D) visualization of the kidney at the whole-mount scale is challenging. In the present study, we optimized mouse whole-mount kidney clearing, which improved the transparency ratio to over 90% based on organ-specific perfusion (OSP)-clear, unobstructed brain imaging cocktails and computational analysis (CUBIC). The optimized OSP-CUBIC-compatible 3D immunostaining and imaging simultaneously visualized the high-resolution 3D structure of the whole-mount renal microvascular, glomerulus, and accompanying wrapped traveling sympathetic nerves in mice. A mouse model of pressure overload-induced heart failure (HF) was then established by minimally invasive transverse aortic constriction (MTAC). Further 3D quantification revealed renal sympathetic hyperinnervation (6.80 ± 1.04% vs. 3.73 ± 0.60%, P < 0.05) in mice with HF. In conclusion, this newly developed whole-organ tissue clearing and imaging system provides comprehensive information at the whole-mount scale and has great potential for kidney research. Our data suggest that renal sympathetic hyperinnervation is involved in HF associated with renal dysfunction.

Incidence, predictors, and clinical impact of bleeding recurrence in patients with prior gastrointestinal bleeding undergoing LAAC

BACKGROUND

Gastrointestinal bleeding (GIB) is associated with a high recurrence rate and a prior GIB episode is common in real-world left atrial appendage closure (LAAC) recipients. The present study sought to evaluate the clinical characteristics and outcomes of patients with prior GIB undergoing LAAC, and to determine the factors associated with and clinical impact of GIB recurrence.

METHODS

Multicenter study including 277 consecutive patients who underwent percutaneous LAAC and had prior GIB. All-cause death, all bleeding, GIB recurrence, and clinical ischemic stroke were recorded.

RESULTS

After a median follow-up of 17 (interquartile range: 6-37) months post-LAAC, the rates of death, bleeding, GIB recurrence, and ischemic stroke were 14.0 per 100 person-year (PY), 29.3 per 100 PY, 17.7 per 100 PY, and 1.1 per 100 PY, respectively. GIB recurrence occurred within 3 months post-LAAC in 55.8% of patients. A previous lower GIB (vs. upper or unclassified) (HR: 1.76; 95% CI: 1.09-2.82; p = .020) and eGFR < 45 mL/min (HR: 1.70; 95% CI:1.04-2.67; p = .033) determined an increased risk of GIB recurrence. By multivariable analysis, eGFR < 45 mL/min (HR: 2.72; 95% CI: 1.70-4.34; p < .001), GIB recurrence following LAAC (HR: 2.15; 95% CI: 1.33-3.46; p = .002), diabetes mellitus (HR: 1.77; 95% CI: 1.10-2.84; p = .018), and age (HR: 1.06; 95% CI: 1.03-1.10; p < .001) were associated with an increased mortality.

CONCLUSIONS

Patients with prior GIB undergoing LAAC exhibited a relatively low rate of GIB recurrence, and prior lower GIB and moderate-to-severe chronic kidney disease determined an increased risk. GIB recurrence was associated with an increased mortality.

Effect of Glomerular Filtration Rates on Outcomes Following Percutaneous Left Atrial Appendage Closure

Scarce data support the prescription of oral anticoagulation in patients with concomitant advanced chronic kidney disease (CKD) and atrial fibrillation, and left atrial appendage closure (LAAC) may provide a favorable risk-benefit ratio in this population. However, outcomes of LAAC in CKD patients are unknown. We aimed to investigate the impact of moderate-to-severe CKD on clinical outcomes following percutaneous LAAC. This was a multicenter study including 1094 patients who underwent LAAC. Moderate-to-severe CKD was defined as an eGFR<45 mL/min. Death, ischemic stroke, severe bleeding (≥BARC 3a) and serious adverse event (SAE; composite of death, stroke or severe bleeding) were recorded. A total of 300 patients (27.4%) had moderate-to-severe CKD. There were no differences between groups in periprocedural complications or device related thrombosis. At a median follow-up of 2 (1 to 3) years, patients with moderate-to-severe CKD did not present an increased risk of ischemic stroke (hazard ratio [HR]: 0.65; 95% confidence interval [CI]: 0.22 to 1.92; p = 0.435) but were at a higher risk of death (HR: 2.84; 95% CI: 2.22 to 3.64; p <0.001), severe bleeding (HR: 1.96; 95% CI: 1.36 to 2.81; p <0.001) and SAE (HR: 2.23; 95% CI: 1.80 to 2.77; p <0.001). By multivariable analysis, an eGFR<45 ml/min (HR: 1.92; 95% CI: 1.34 to 2.76; p <0.001) and previous bleeding (HR: 2.30; 95% CI: 1.27 to 4.17; p = 0.006) were associated with an increased risk of severe bleeding. In conclusion, patients with moderate-to-severe CKD who underwent LAAC had very high thrombotic and bleeding risks. Although the rates of device related thrombosis or ischemic stroke after-LAAC were not influenced by kidney dysfunction, patients with moderate-to-severe CKD remained at higher risk of severe bleeding events.

Thromboembolic and Bleeding Risk in Atrial Fibrillation Patients with Chronic Kidney Disease: Role of Anticoagulation Therapy

Atrial fibrillation (AF) and chronic kidney disease (CKD) are strictly related; several independent risk factors of AF are often frequent in CKD patients. AF prevalence is very common among these patients, ranging between 15% and 20% in advanced stages of CKD. Moreover, the results of several studies showed that AF patients with end stage renal disease (ESRD) have a higher mortality rate than patients with preserved renal function due to an increased incidence of stroke and an unpredicted elevated hemorrhagic risk. Direct oral anticoagulants (DOACs) are currently contraindicated in patients with ESRD and vitamin K antagonists (VKAs), remaining the only drugs allowed, although they show numerous critical issues such as a narrow therapeutic window, increased tissue calcification and an unfavorable risk/benefit ratio with low stroke prevention effect and augmented risk of major bleeding. The purpose of this review is to shed light on the applications of DOAC therapy in CKD patients, especially in ESRD patients.

Immunohistochemistry of Kidney a-SMA, Collagen 1, and Collagen 3, in A Novel Mouse Model of Reno-cardiac Syndrome

Cardiorenal syndrome defines a synergistic pathology of the heart and kidneys where failure of one organ causes failure in the other. The incidence of cardiovascular mortality caused by this syndrome, is 20 fold higher in the end stage renal disease (ESRD) population compared to the population as a whole thus necessitating the need for improved therapeutic strategies to combat reno-cardiac pathologies. Murine in vivo models play a major role in such research permitting precise genetic modification thus reducing miscellany, however presently there is no steadfast model of reno-cardiac syndrome in the most common genetically modified mouse strain, the C57BL/6 mouse. In this study we have modified an established model of chronic renal disease using adenine diet and extended the associated pathology achieving chronic renal failure and consequent reno-cardiac syndrome in the C57BL/6 mouse. Eight week-old male C57BL/6 mice were acclimatized for 7 days before administration of a 0.15% adenine diet or control diet for 20 weeks after which the experiment was terminated and blood, urine and organs were collected and analyzed biochemically and by immunohistochemistry. Administration of 0.15% adenine diet caused progressive renal failure resulting in a reno-cardiac syndrome confirmed by a significantly increased heart to body weight ratio (P < 0.0001). Blood biochemistry showed that adenine fed mice had significantly increased serum creatinine, urea (P < 0.0001), and a significantly reduced glomerular filtration rate (P < 0.05), while immunohistochemistry of the kidneys for α-SMA, collagen 1 and collagen 3 showed severe fibrosis. We present a novel regimen of adenine diet which induces both chronic kidney disease and reno-cardiac syndrome in the C57BL/6 mouse strain. The non-surgical nature of this model makes it highly reproducible compared to other models currently available.

[Low serum Klotho level as a predictor of calcification of the heart and blood vessels in patients with CKD stages 2-5D]

Cardiovascular calcification (CVC) makes a significant contribution to the manifestation of cardiovascular complications in patients with chronic kidney disease. Early CVC markers are currently being actively studied to optimize cardio-renoprotective strategies. We performed a prospective comparative analysis of the following factors: FGF-23, a-Klotho, sclecrostin, phosphate, parathyroid hormone, the estimated glomerular filtration rate (eGFR), central systolic pressure as an independent determinant of CVC.

MATERIALS AND METHODS

The study included 131 patients with chronic kidney disease 25D st. Serum levels of FGF-23, Klotho, and sclerostin were evaluated using the ELISA method. Vascular augmentation (stiffness) indices, central arterial pressure (using the SphygmoCor device), calcification of heart valves and the degree of aortic calcification (aortic radiography) were also investigated. The observation period was 2 years.

RESULTS

According to the Spearman correlation analysis, the percent of calcification increase and the change in Klotho level are most related. According to ROC analysis, a decrease in serum levels of Klotho by 50 units or more is a significant predictor of an increase in aortic calcification of 50% or more with a sensitivity of 86% and a specificity of 77%. Using logistic regression analysis, it was found that a serum Klotho level 632 pg/L predicts an eGFR below a median level of 48 ml/min/1.73 m2 with a sensitivity of 85.5% and a specificity of 78.5%. Wherein OR 17.477 (CI 95% 8.04637.962; p0.001).

CONCLUSION

The factor most associated with CVC is Klotho. Decreased serum level of Klotho is a predictor of aortic calcification. In addition, the initial serum level of Klotho is a predictor of eGFR after 2 years.

Anticoagulation in Concomitant Chronic Kidney Disease and Atrial Fibrillation: JACC Review Topic of the Week

Atrial fibrillation (AF) and chronic kidney disease (CKD) often coexist as they share multiple risk factors, including hypertension, diabetes mellitus, and coronary artery disease. Although there is irrefutable evidence supporting anticoagulation in AF in the general population, these data may not be transferable to the setting of advanced CKD, where the decision to commence anticoagulation poses a conundrum. In this cohort, there is a progressively increased risk of both ischemic stroke and hemorrhage as renal function declines, complicating the decision to initiate anticoagulation. No definitive clinical guidelines derived from randomized controlled trials exist to aid clinical decision-making, and the findings from observational studies are conflicting. In this review, the authors outline the pathophysiological mechanisms at play and summarize the limited existing data related to anticoagulation in those with concomitant CKD and AF. Finally, the authors suggest how to approach the decision of whether and how to use oral anticoagulation in these patients.

Cardiorenal syndrome: Multi-organ dysfunction involving the heart, kidney and vasculature

Cardiorenal syndrome (CRS) is a multi-organ disease, encompassing heart, kidney and vascular system dysfunction. CRS is a worldwide problem, with high morbidity, mortality, and inflicts a significant burden on the health care system. The pathophysiology is complex, involving interactions between neurohormones, inflammatory processes, oxidative stress and metabolic derangements. Therapies remain inadequate, mainly comprising symptomatic care with minimal prospect of full recovery. Challenges include limiting the contradictory effects of multi-organ targeted drug prescriptions and continuous monitoring of volume overload. Novel strategies such as multi-organ transplantation and innovative dialysis modalities have been considered but lack evidence in the CRS context. The adjunct use of pharmaceuticals targeting alternative pathways showing positive results in preclinical models also warrants further validation in the clinic. In recent years, studies have identified the involvement of gut dysbiosis, uraemic toxin accumulation, sphingolipid imbalance and other unconventional contributors, which has encouraged a shift in the paradigm of CRS therapy.

Clinical and functional patient characteristics predict medical needs in older patients at risk of functional decline

Background

The rising number of older multimorbid in-patients has implications for medical care. There is a growing need for the identification of factors predicting the needs of older patients in hospital environments. Our aim was to evaluate the use of clinical and functional patient characteristics for the prediction of medical needs in older hospitalized patients.

Methods

Two hundred forty-two in-patients (57.4% male) aged 78.4 ± 6.4 years, who were consecutively admitted to internal medicine departments of the University Hospital Essen between July 2015 and February 2017, were prospectively enrolled. Patients were assessed upon admission using the Identification of Seniors at Risk (ISAR) screening followed by comprehensive geriatric assessment (CGA). The CGA included standardized instruments for the assessment of activities of daily living (ADL), cognition, mobility, and signs of depression upon admission. In multivariable regressions we evaluated the association of clinical patient characteristics, the ISAR score and CGA results with length of hospital stay, number of nursing hours and receiving physiotherapy as indicators for medical needs. We identified clinical characteristics and risk factors associated with higher medical needs.

Results

The 242 patients spent [median(Q1;Q3)]:9.0(4.0;16.0) days in the hospital, needed 2.0(1.5;2.7) hours of nursing each day, and 34.3% received physiotherapy.

In multivariable regression analyses including clinical patient characteristics, ISAR and CGA domains, the factors age (β = − 0.19, 95% confidence interval (CI) = − 0.66;-0.13), number of admission diagnoses (β = 0.28, 95% CI = 0.16;0.41), ADL impairment (B = 6.66, 95% CI = 3.312;10.01), and signs of depression (B = 6.69, 95% CI = 1.43;11.94) independently predicted length of hospital stay. ADL impairment (B = 1.14, 95%CI = 0.67;1.61), cognition impairment (B = 0.57, 95% CI = 0.07;1.07) and ISAR score (β =0.26, 95% CI = 0.01;0.28) independently predicted nursing hours. The number of admission diagnoses (risk ratio (RR) = 1.06, 95% CI = 1.04;1.08), ADL impairment (RR = 3.54, 95% CI = 2.29;5.47), cognition impairment (RR = 1.77, 95% CI = 1.20;2.62) and signs of depression (RR = 1.99, 95% CI = 1.39;2.85) predicted receiving physiotherapy.

Conclusion

Among older in-patients at risk for functional decline, the number of comorbidities, reduced ADL, cognition impairment and signs of depression are important predictors of length of hospital stay, nursing hours, and receiving physiotherapy during hospital stay.

Impact of hepatitis virus infection on arterial calcification among incident hemodialysis patients

BACKGROUND

The impact of hepatitis virus infection on arterial calcification (AC) was not studied.

OBJECTIVE

To study the prevalence, severity and distribution of AC in incident hemodialysis patients with hepatitis B and C viral infection.

CASES AND METHODS

172 stage 5 CKD adults (98 male and 74 female) were included; 58 of them were seronegative for both hepatitis B and C (SN group), 48 were positive for hepatitis B virus infection (HBV group) and 66 were hepatitis C virus positive (HCV group). Beside histopathology of the obtained arterial samples, all these cases were examined for body mass index (BMI), serum calcium (Ca), phosphorus (P), alkaline phosphatase (AP), serum albumin, uric acid (UA), alanine transaminase (ALT), parathormone (PTH), fibroblast growth factor 23(FGF23), interleukin 6 (IL6), and 25 hydroxy vitamin D (25 (OH) vit D), hemoglobin concentration, and serum ferritin.

RESULTS

86 (50%) of the cases had AC; 11 of them were in SN group (19%), 9 in HBV group (18.8%) and all the 66 HCV group (100%). In SN group, 4 had intimal calcification, 5 had medial calcification, and 2 had both intimal and medial calcification. In HBV group, 9 had intimal calcification, while no cases were encountered with either medial or both site calcifications. In HCV group, 16 had intimal calcification, 31 had medial calcification, and 19 had both intimal and medial calcification. Calcification was in the form of spots in one case in SN group, and 6 cases in HBV group, a single plaque of calcification in 5 cases of SN group, 3 cases of HBV group, and 16 cases of HCV group, multiple plaques were detected in 4 cases in SN group, and 31 cases in HCV group, and diffuse calcification in one case in SN group, and 19 cases in HCV group. In HBV group, calcification was only detected in patients with high viremia, while all patients with low or moderate viremia were devoid of calcification. In HCV group, all patients with low viremia had intimal solitary plaque of calcification, all patients with moderate viremia had multiple plaques of medial calcification, while all patients with high viremia had diffuse intimal and medial calcification. Both groups of viral hepatitis were significantly different in comparison to SN group in either distribution or calcification score (P<0.001 in all). HBV group had significantly lower serum P, CaxP and PTH in comparison to SN group (4.6±0.66 vs. 5.45±0.77mg/dL, 36.4±7.2 vs. 44.1±8.69, and 348±65.4 vs. 405.9±83.2pg/mL, P<0.001, <0.001, and 0.035 respectively). On the other hand, HCV group did not show any significant difference in any of the studied parameters compared to SN group.

CONCLUSION

HCV positive patients are more prone to develop AC that is more extensive. HBV positive patients were less likely to have arterial medial calcification, probably related to lower serum phosphorus, CaxP product and PTH. HCV infection should be added as risk factor for AC among CKD patients. Further studies are needed to confirm these findings.

Health outcome of older hospitalized patients in internal medicine environments evaluated by Identification of Seniors at Risk (ISAR) screening and geriatric assessment

Background

Hospitals are in need of valid and economic screening and assessment tools that help identifying older patients at risk for complications which require intensified support during their hospital stay.

Methods

Five hundred forty-seven internal medicine in-patients (mean age 78.14 ± 5.96 years; 54.7% males) prospectively received Identification of Seniors at Risk (ISAR) screening. If screening results were positive (ISAR score ≥ 2), a comprehensive geriatric assessment (CGA) was performed. We explored sensitivity and specificity of different ISAR and CGA cutoffs. Further, we analyzed the risk of falls and how patients got discharged from hospital.

Results

ISAR+/CGA abnormal patients spent more days in hospital (16.1 ± 14.5), received more nursing hours per day (3.0 ± 2.3), more hours of physiotherapy during their hospital stay (2.2 ± 3.2), and had more falls (10.1%) compared to ISAR+/CGA normal (10.9 ± 12.3, 2.0 ± 1.2, 1.2 ± 4.3, and 2.8%, respectively, all p ≤ 0.016) and ISAR- (9.6 ± 11.5, 2.3 ± 4.5, 0.7 ± 2.0, and 2.2%, respectively, all p ≤ 0.002) patients. ISAR+/CGA abnormal patients terminated their treatment regularly with being discharged back home less often (59.6%) compared to ISAR+/CGA normal (78.5%, p = 0.002) and ISAR- (78.2%, p = 0.056) patients. ISAR cutoff≥2 and CGA defined as abnormal in case of impairment of ADL plus another CGA domain achieved best sensitivity/specificity.

Conclusions

Abnormal geriatric risk screening and assessment are associated with longer hospital stay and higher amount of nursing and physiotherapy during hospital stay, greater risk of falling, and a lower percentage of successfully terminated treatment in older in-patients.

Potential Role of H-Ferritin in Mitigating Valvular Mineralization

Objective- Calcific aortic valve disease is a prominent finding in elderly and in patients with chronic kidney disease. We investigated the potential role of iron metabolism in the pathogenesis of calcific aortic valve disease. Approach and Results- Cultured valvular interstitial cells of stenotic aortic valve with calcification from patients undergoing valve replacement exhibited significant susceptibility to mineralization/osteoblastic transdifferentiation in response to phosphate. This process was abrogated by iron via induction of H-ferritin as reflected by lowering ALP and osteocalcin secretion and preventing extracellular calcium deposition. Cellular phosphate uptake and accumulation of lysosomal phosphate were decreased. Accordingly, expression of phosphate transporters Pit1 and Pit2 were repressed. Translocation of ferritin into lysosomes occurred with high phosphate-binding capacity. Importantly, ferritin reduced nuclear accumulation of RUNX2 (Runt-related transcription factor 2), and as a reciprocal effect, it enhanced nuclear localization of transcription factor Sox9 (SRY [sex-determining region Y]-box 9). Pyrophosphate generation was also increased via upregulation of ENPP2 (ectonucleotide pyrophosphatase/phosphodiesterase-2). 3H-1, 2-dithiole-3-thione mimicked these beneficial effects in valvular interstitial cell via induction of H-ferritin. Ferroxidase activity of H-ferritin was essential for this function, as ceruloplasmin exhibited similar inhibitory functions. Histological analysis of stenotic aortic valve revealed high expression of H-ferritin without iron accumulation and its relative dominance over ALP in noncalcified regions. Increased expression of H-ferritin accompanied by elevation of TNF-α (tumor necrosis factor-α) and IL-1β (interleukin-1β) levels, inducers of H-ferritin, corroborates the essential role of ferritin/ferroxidase via attenuating inflammation in calcific aortic valve disease. Conclusions- Our results indicate that H-ferritin is a stratagem in mitigating valvular mineralization/osteoblastic differentiation. Utilization of 3H-1, 2-dithiole-3-thione to induce ferritin expression may prove a novel therapeutic potential in valvular mineralization.

Chronic kidney disease induces left ventricular overexpression of the pro-hypertrophic microRNA-212

Chronic kidney disease (CKD) is a public health problem that increases the risk of cardiovascular morbidity and mortality. Heart failure with preserved ejection fraction (HFpEF) characterized by left ventricular hypertrophy (LVH) and diastolic dysfunction is a common cardiovascular complication of CKD. MicroRNA-212 (miR-212) has been demonstrated previously to be a crucial regulator of pathologic LVH in pressure-overload-induced heart failure via regulating the forkhead box O3 (FOXO3)/calcineurin/nuclear factor of activated T-cells (NFAT) pathway. Here we aimed to investigate whether miR-212 and its hypertrophy-associated targets including FOXO3, extracellular signal-regulated kinase 2 (ERK2), and AMP-activated protein kinase (AMPK) play a role in the development of HFpEF in CKD. CKD was induced by 5/6 nephrectomy in male Wistar rats. Echocardiography and histology revealed LVH, fibrosis, preserved systolic function, and diastolic dysfunction in the CKD group as compared to sham-operated animals eight and/or nine weeks later. Left ventricular miR-212 was significantly overexpressed in CKD. However, expressions of FOXO3, AMPK, and ERK2 failed to change significantly at the mRNA or protein level. The protein kinase B (AKT)/FOXO3 and AKT/mammalian target of rapamycin (mTOR) pathways are also proposed regulators of LVH induced by pressure-overload. Interestingly, phospho-AKT/total-AKT ratio was increased in CKD without significantly affecting phosphorylation of FOXO3 or mTOR. In summary, cardiac overexpression of miR-212 in CKD failed to affect its previously implicated hypertrophy-associated downstream targets. Thus, the molecular mechanism of the development of LVH in CKD seems to be independent of the FOXO3, ERK1/2, AMPK, and AKT/mTOR-mediated pathways indicating unique features in this form of LVH.

A novel model of reno-cardiac syndrome in the C57BL/ 6 mouse strain

Background

The end stage renal disease population has a 20 fold higher incidence of cardiovascular mortality compared to the overall population. The development of reno-cardiac syndrome in these patients will result in cardiovascular events to be the cause of 50% of fatalities. There is therefore a need to research improved therapeutic strategies to combat renal cardiac pathologies. Murine in vivo models contribute greatly to such research allowing for specific genetic modification and reduced miscellany, however there is currently no reliable model of reno-cardiac syndrome in the most common genetically modified mouse strain, the C57BL/6. In this study we have manipulated an established model of chronic renal disease using adenine infused diet and prolonged the course of its pathology achieving chronic renal failure and subsequent reno-cardiac syndrome in the C57BL/6 mouse.

Methods

Eight week-old male C57BL/ 6 mice were acclimatised for 7 days before administration of a 0.15% adenine diet or control diet for 20 weeks.

Cardiac function was assessed in mice at week 20 by echocardiography. At experiment termination blood and urine samples were analysed biochemically and organ dysfunction/injury was determined using immunoblotting and immunohistochemistry.

Results

Administration of 0.15% adenine diet caused progressive renal failure resulting in reno-cardiac syndrome. At endpoint uraemia was confirmed by blood biochemistry which in the adenine fed mice showed significant increases in serum creatinine, urea, calcium (P < 0.0001) potassium (P < 0.05), and a significantly reduced glomerular filtration rate (P < 0.05). Reno-cardiac syndrome was confirmed by a significantly increased heart to body weight ratio (P < 0.0001) and echocardiography which showed significant reductions in percentage of ejection fraction, fractional shortening, fractional area change, (P < 0.0001) and an increase in left ventricular end diastolic volume (P < 0.05). Immunoblotting of kidney and heart tissue showed increased apoptosis (caspase 3) and fibrosis (fibronectin) and increases in the cardiac levels of phosphorylated Akt, and renal total Akt. Immunohistochemistry for α-SMA, collagen 1 and collagen 3 further confirmed fibrosis.

Conclusions

We present a novel regimen of adenine diet which induces both chronic kidney disease and reno-cardiac syndrome in the C57/BL6 mouse strain. The non-surgical nature of this model makes it highly reproducible compared to other models currently available.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1155-3) contains supplementary material, which is available to authorized users.

Mechanisms and Modulation of Oxidative/Nitrative Stress in Type 4 Cardio-Renal Syndrome and Renal Sarcopenia

Chronic kidney disease (CKD) is a public health problem and a recognized risk factor for cardiovascular diseases (CVD). CKD could amplify the progression of chronic heart failure leading to the development of type 4 cardio-renal syndrome (T4CRS). The severity and persistence of heart failure are strongly associated with mortality risk in T4CRS. CKD is also a catabolic state leading to renal sarcopenia which is characterized by the loss of skeletal muscle strength and physical function. Renal sarcopenia also promotes the development of CVD and increases the mortality in CKD patients. In turn, heart failure developed in T4CRS could result in chronic muscle hypoperfusion and metabolic disturbances leading to or aggravating the renal sarcopenia. The interplay of multiple factors (e.g., comorbidities, over-activated renin-angiotensin-aldosterone system [RAAS], sympathetic nervous system [SNS], oxidative/nitrative stress, inflammation, etc.) may result in the progression of T4CRS and renal sarcopenia. Among these factors, oxidative/nitrative stress plays a crucial role in the complex pathomechanism and interrelationship between T4CRS and renal sarcopenia. In the heart and skeletal muscle, mitochondria, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, uncoupled nitric oxide synthase (NOS) and xanthine oxidase are major ROS sources producing superoxide anion (O2^·−) and/or hydrogen peroxide (H₂O₂). O2^·− reacts with nitric oxide (NO) forming peroxynitrite (ONOO⁻) which is a highly reactive nitrogen species (RNS). High levels of ROS/RNS cause lipid peroxidation, DNA damage, interacts with both DNA repair enzymes and transcription factors, leads to the oxidation/nitration of key proteins involved in contractility, calcium handling, metabolism, antioxidant defense mechanisms, etc. It also activates the inflammatory response, stress signals inducing cardiac hypertrophy, fibrosis, or cell death via different mechanisms (e.g., apoptosis, necrosis) and dysregulates autophagy. Therefore, the thorough understanding of the mechanisms which lead to perturbations in oxidative/nitrative metabolism and its relationship with pro-inflammatory, hypertrophic, fibrotic, cell death and other pathways would help to develop strategies to counteract systemic and tissue oxidative/nitrative stress in T4CRS and renal sarcopenia. In this review, we also focus on the effects of some well-known and novel pharmaceuticals, nutraceuticals, and physical exercise on cardiac and skeletal muscle oxidative/nitrative stress in T4CRS and renal sarcopenia.

Dissecting recipient from donor contribution in experimental kidney transplantation: focus on endothelial proliferation and inflammation

Kidney transplantation (Tx) is considered the only definite treatment for end-stage kidney disease (ESKD) patients. The increasing prevalence of ESKD has necessitated the introduction of transplantation with kidneys from suboptimal donors. There is, however, still a lack of fundamental and longitudinal research on suboptimal kidney transplants. Specifically, there is a demand for accurate pre-Tx predictors of donor kidney function and injury to predict post-Tx outcome. In the present study, we combine rat models of chronic kidney disease (CKD) and renal Tx to dissect the effects of healthy and CKD renal grafts on healthy and CKD recipients. We show that renal function at 6 weeks post-Tx is exclusively determined by donor graft quality. Using cell tracking within enhanced green fluorescent protein-positive (eGFP⁺) recipients, we furthermore show that most inflammatory cells within the donor kidney originate from the donor. Oxidative and vascular extra-renal damage were, in contrast, determined by the recipient. Post- versus pre-Tx evaluation of grafts showed an increase in glomerular and peritubular capillary rarefaction in healthy but not CKD grafts within a CKD environment. Proliferation of glomerular endothelium was similar in all groups, and influx of eGFP⁺ recipient-derived cells occurred irrespective of graft or recipient status. Glomerular and peritubular capillary rarefaction, severity of inflammation and macrophage subtype data post-Tx were, however, determined by more complicated effects, warranting further study. Our experimental model could help to further distinguish graft from recipient environment effects, leading to new strategies to improve graft survival of suboptimal Tx kidneys.

This article has an associated First Person interview with the first author of the paper.

Summary: Using experimental kidney transplantation, we dissected donor graft from recipient environment effects, focusing on the endothelium and inflammation. These results can direct strategies to improve graft survival after suboptimal transplantation.

Is Sclerostin Level Associated with Cardiovascular Diseases in Hemodialysis Patients?

BACKGROUND/AIMS

The objective of this study is to evaluate the relation between sclerostin, arterial stiffness, and cardiovascular events (CVE) in hemodialysis patients (HD).

METHODS

Sclerostin level and carotid-femoral pulse wave velocity (PWV) in 97 HD patients and sclerostin level in 40 controls were measured.

RESULTS

Sclerostin level was significantly higher in patients than in controls. Sclerostin associated positively with age, male gender, cardiovascular disease, statin use, BMI, and PWV while negatively with alkaline phosphatase, parathormone (PTH), Kt/V, cinacalcet and vitamin D use in univariable correlation analyses. Sclerostin associated positively with male gender and statin use but negatively with PTH in multivariate regression analyses. During observation, 30 fatal or nonfatal CVEs were observed. While univariate correlation analysis showed a positive association between PWV and sclerostin, there was no relation between the two in multivariate regression analysis.

CONCLUSION

Further studies are needed to understand the role of sclerostin in predicting PWV changes in HD patients.

Is Fibroblast growth factor 23 the leading cause of increased mortality among chronic kidney disease patients? A narrative review

The death rate among chronic kidney disease patients is the highest compared to other chronic diseases. 60% of these fatalities are cardiovascular. Cardiovascular calcifications and chronic inflammation affect almost all chronic kidney disease patients and are associated with cardiovascular mortality. Fibroblast growth factor 23 is associated with vascular calcification. Systemic inflammation in chronic kidney disease patients is multifactorial. The role of systemic inflammation in the pathogenesis of vascular calcification was recently reappraised. Fibroblast growth factor 23 was accused as a direct stimulus of left ventricular hypertrophy, uremic inflammation, and impaired neutrophil function. This review will discuss the underlying mechanisms that underlie the link between Fibroblast growth factor 23 and increased mortality encountered among chronic kidney disease patients.

Effect of Omega-3 Fatty Acids on Serum Lipid Profile and Oxidative Stress in Pediatric Patients on Regular Hemodialysis: A Randomized Placebo-Controlled Study

OBJECTIVE

We sought to evaluate the effects of omega-3 fatty acids supplementation on serum lipid profile and oxidative stress markers in pediatric patients with end-stage renal disease on regular hemodialysis (HD).

DESIGN

This study was a double-blinded, randomized, placebo-controlled trial conducted on 49 pediatric patients on regular HD for at least 6 months.

INTERVENTION

Patients were randomly divided into either omega-3 group (n = 25) who received 1-g oral omega-3 capsule once daily for 16 weeks or placebo group (n = 24) who received 1-g matching oral placebo capsule once daily for 16 weeks.

MAIN OUTCOME MEASURE

Lipid profile markers including: total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and oxidative stress markers including the following: malondialdehyde, glutathione peroxidase, and superoxide dismutase were measured at baseline and after 16 weeks of supplementation.

RESULTS

By the end of the study, children in omega-3 group showed a highly significant reduction in total cholesterol and a highly significant increase in glutathione peroxidase and superoxide dismutase levels.

CONCLUSION

The administration of omega-3 has a beneficial effect on serum lipid profile and oxidative stress in children undergoing HD.

Mode of renal replacement therapy determines endotoxemia and neutrophil dysfunction in chronic kidney disease

Bacterial infection and sepsis are common complications of chronic kidney disease (CKD). A vicious cycle of increased gut permeability, endotoxemia, inadequate activation of the innate immune system and resulting innate immune dysfunction is hypothesized. We assessed endotoxemia, neutrophil function and its relation to oxidative stress, inflammation and gut permeability in patients with CKD grade 3–5 without renal replacement therapy (CKD group, n = 57), patients with CKD stage 5 undergoing haemodialysis (HD, n = 32) or peritoneal dialysis (PD, n = 28) and patients after kidney transplantation (KT, n = 67) in a cross-sectional observational study. In HD patients, endotoxin serum levels were elevated and neutrophil phagocytic capacity was decreased compared to all other groups. Patients on HD had a significantly higher mortality, due to infections during follow up, compared to PD (p = 0.022). Oxidative stress, neutrophil energy charge, systemic inflammation and gut permeability could not completely explain these differences. Our findings suggest that dialysis modality and not renal function per se determine the development of neutrophil dysfunction and endotoxemia in CKD-patients. HD patients are particularly prone to neutrophil dysfunction and endotoxemia whereas neutrophil function seems to improve after KT. Multi-target approaches are therefore warranted to improve neutrophil function and potentially reduce the rate of infections with patients undergoing haemodialysis.

Type 4 cardiorenal syndrome

The Acute Dialysis Quality Initiative consensus conference proposed a classification of cardiorenal syndrome (CRS), aiming for a better delineation of each subtype. Although the exact pathophysiology of type 4 CRS is not completely understood, the mechanisms involved are probably multifactorial. There is growing evidence that oxidative stress is a major connector in the development and progression of type 4 CRS. Giving its complexity, poor prognosis and increasing incidence, type 4 CRS is becoming a significant public health problem. Patients with chronic kidney disease are particularly predisposed to cardiac dysfunction, due to the high prevalence of traditional cardiovascular risk factors in this population, but the contribution of risk factors specific to chronic kidney disease should also be taken into account. Much remains to be elucidated about type 4 CRS: despite progress over the last decade, there are still significant questions regarding its pathophysiology and there is as yet no specific therapy. A better understanding of the mechanisms involved may provide potential targets for intervention. The present review will provide a brief description of the definition, epidemiology, diagnosis, prognosis, biomarkers and management strategies of type 4 CRS, and the pathophysiological mechanisms and risk factors presumably involved in its development will be particularly highlighted.

Vascular calcification: When should we interfere in chronic kidney disease patients and how?

Chronic kidney disease (CKD) patients are endangered with the highest mortality rate compared to other chronic diseases. Cardiovascular events account for up to 60% of the fatalities. Cardiovascular calcifications affect most of the CKD patients. Most of this calcification is related to disturbed renal phosphate handling. Fibroblast growth factor 23 and klotho deficiency were incriminated in the pathogenesis of vascular calcification through different mechanisms including their effects on endothelium and arterial wall smooth muscle cells. In addition, deficient klotho gene expression, a constant feature of CKD, promotes vascular pathology and shares in progression of the CKD. The role of gut in the etio-pathogenesis of systemic inflammation and vascular calcification is a newly discovered mechanism. This review will cover the medical history, prevalence, pathogenesis, clinical relevance, different tools used to diagnose, the ideal timing to prevent or to withhold the progression of vascular calcification and the different medications and medical procedures that can help to prolong the survival of CKD patients.

The impact of intervention strategies that target arterial stiffness in end-stage renal disease: a systematic review protocol

BACKGROUND/OBJECTIVES

Vascular damage contributes to the high cardiovascular morbidity and mortality in end-stage renal disease (ESRD). Increased aortic stiffness measured by carotid-femoral pulse wave velocity (cf-PWV) is a strong and independent predictor of the cardiovascular risk in ESRD patients. Recently, there has been considerable interest in developing strategies to lessen the progression of arterial stiffness in ESRD patients using cf-PWV as a tool to monitor therapeutic responses, but their benefit on the long-term cardiovascular risk is not known. Appraisal of the effects of existing stiffness-based interventions on the cf-PWV would facilitate selecting optimal therapies to be tested in randomized clinical trials. The aim of this systematic review will be to evaluate the impact of arterial stiffness-based interventions on the cf-PWV in ESRD patients. Secondarily, for each intervention, we will determine the minimal duration needed to achieve a significant reduction of cf-PWV, the minimal cf-PWV reduction threshold or effect size, and adverse events.

METHODS/DESIGN

This review will be conducted using MEDLINE, EMBASE, and EBM Reviews. We will select clinical trials and observational studies (cohort, case-control, and before/after studies and case series) that evaluated pharmacologic or non-pharmacologic interventions in which the primary effect is to improve structural and/or dynamic components of arterial stiffness in adults with stage 5 chronic kidney disease. The primary outcome of interest will be cf-PWV. Study selection and data collection will be performed by two reviewers. Validated tools will be used to assess the methodological quality and risk of bias among different study designs. We will describe all included citations according to study characteristics, methodological quality, and outcomes. Suitability for meta-analysis will be determined by the degree of clinical and statistical heterogeneity between studies. If appropriate, we will calculate effect estimates by obtaining the relative risks with 95 % confidence intervals pooled according to study design using a random effects model.

DISCUSSION

This review will summarize evidence regarding effects of interventions targeting arterial stiffness in ESRD patients. Our results will inform clinicians and researchers on the type of existing arterial stiffness-based interventions for ESRD patients and their potential efficacy and safety, with a goal to guide future clinical trials aimed at reducing adverse cardiovascular events.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016033463.

Vitamin E supplementation fails to impact measures of oxidative stress or the anaemia of feline chronic kidney disease: a randomised, double-blinded placebo control study

This study was designed to test the hypothesis that supplementation with vitamin E, an antioxidant, in cats with chronic kidney disease (CKD), would reduce oxidative stress and its impact on RBC membrane fragility, resulting in these cats maintaining a greater packed cell volume (PCV) compared with CKD cats not receiving supplementation.

Thirty‐six cats with CKD were randomly assigned to receive either daily vitamin E or a placebo for 3 months in a double‐blinded study design.

History and physical examination, blood pressure, complete blood count (CBC), PCV, biochemical profile and urinalysis (UA) were determined. Parameters of oxidative stress and osmotic fragility were measured. Cats were administered vitamin E or placebo once daily for 3 months. Cats were then reassessed and the diagnostics were repeated.

Twenty‐four cats completed the study, 11 in the vitamin E group and 13 in the placebo group. There were no significant differences between the two groups at the start, or upon completion of the study with regard to biochemical parameters, oxidative stress, erythrocyte osmotic fragility or PCV. None of these parameters changed significantly in either group over the treatment period.

Daily supplementation with 30 IU of vitamin E did not affect the measures of oxidative stress or the anaemia seen in cats with CKD.

Long-term follow-up of blood pressure and glomerular filtration rate in patients with a solitary functioning kidney: a comparison between Wilms tumor survivors and nephrectomy for other reasons

BACKGROUND

Children with unilateral Wilms tumor (WT) treated with chemotherapy and/or radiotherapy and nephrectomy have excellent survival rates. A solitary functioning kidney (SFK) is associated with progressive renal injury. This study aims to investigate the additional effect of Wilms tumor treatment on renal function compared with children with an SFK for non-oncological reasons.

METHODS

A single-center retrospective cohort study on the renal injury markers of 79 survivors of unilateral WT was performed and compared with a matched group of children with an SFK for non-oncological reasons. Mean age at follow-up was 12.4 (SD 5.9) years.

RESULTS

During follow-up, mean estimated glomerular filtration rate (eGFR) and blood pressure z-scores remained stable at an acceptable level. However, in the group of 31 WT patients with a follow-up of 15 years, 23% showed signs of renal injury. This proportion was smaller than the 54% in a group of SFK patients based on non-oncological causes (p = 0.004).

CONCLUSIONS

A significant proportion of WT survivors develop renal injury during follow-up. Our data may be an underestimation of the true frequency of progressive renal injury, due to a lack of information on proteinuria. As with patients with a non-oncological SFK, long-term follow-up is essential to monitor WT survivors.

Prognosis after maternal placental events and revascularization: PAMPER study

BACKGROUND

Middle-aged women are at higher risk than men of death after coronary artery revascularization. Maternal placental syndromes (gestational hypertension, preeclampsia, placental abruption, and placental infarction) are associated with premature coronary artery disease, but their influence on survival after coronary artery revascularization is unknown.

OBJECTIVE

The purpose of this study was to determine whether a history of maternal placental syndromes alters the risk of death after coronary artery revascularization in middle-aged women.

STUDY DESIGN

We completed a population-based retrospective cohort study among all hospitals in Ontario, Canada, where universal health care includes all aspects of antenatal and delivery care as well as all outpatient and inpatient health care, which includes coronary revascularization. We included 1985 middle-aged women who underwent a first percutaneous coronary intervention or coronary artery bypass grafting between 1993 and 2012 and who had ≥1 previous delivery. We excluded those with cardiovascular disease ≤1 year before or coronary revascularization ≤90 days after any delivery. The main study outcome, determined a priori, was all-cause death. Hazard ratios were adjusted for age, socioeconomic status, parity, revascularization type, time since last delivery, hypertension, diabetes mellitus, obesity, dyslipidemia, tobacco or drug dependence, and kidney disease.

RESULTS

Three hundred sixty-two of 1985 women (18.2%) who underwent coronary artery revascularization had a previous maternal placental syndrome event. The mean age at index coronary revascularization was 45 years; percutaneous coronary intervention comprised approximately 80% of procedures. After a mean follow-up time of approximately 5 years, 41 deaths (2.2 per 100 person-years) occurred in women with previous maternal placental syndromes and 83 deaths (1.1 per 100 person-years) in women without maternal placental syndrome (adjusted hazard ratio, 1.96; 95% confidence interval, 1.29-2.99). Of the maternal placental syndrome subtypes, the risk of death was significant in women with placental abruption (adjusted hazard ratio, 2.79; 95% confidence interval, 1.31-5.96), placental infarction (adjusted hazard ratio, 3.09; 95% confidence interval, 1.23-7.74), and preeclampsia (adjusted hazard ratio, 1.61; 95% confidence interval, 1.00-2.58). Women with maternal placental syndrome in ≥2 pregnancies had the highest adjusted hazard ratio of death (4.31; 95% confidence interval, 1.71-10.89).

CONCLUSION

In middle-aged women who undergo coronary revascularization, previous maternal placental syndrome doubles the risk of death; recurrent maternal placental syndrome quadruples that risk. Some covariates and secondary measures may not have been well-captured and classified herein, leading to residual confounding.

Pharmacological induction of ferritin prevents osteoblastic transformation of smooth muscle cells

Vascular calcification is a frequent complication of atherosclerosis, diabetes and chronic kidney disease. In the latter group of patients, calcification is commonly seen in tunica media where smooth muscle cells (SMC) undergo osteoblastic transformation. Risk factors such as elevated phosphorus levels and vitamin D3 analogues have been identified. In the light of earlier observations by our group and others, we sought to inhibit SMC calcification via induction of ferritin. Human aortic SMC were cultured using β-glycerophosphate with activated vitamin D3 , or inorganic phosphate with calcium, and induction of alkaline phosphatase (ALP) and osteocalcin as well as accumulation of calcium were used to monitor osteoblastic transformation. In addition, to examine the role of vitamin D3 analogues, plasma samples from patients on haemodialysis who had received calcitriol or paricalcitol were tested for their tendency to induce calcification of SMC. Addition of exogenous ferritin mitigates the transformation of SMC into osteoblast-like cells. Importantly, pharmacological induction of heavy chain ferritin by 3H-1,2-Dithiole-3-thione was able to inhibit the SMC transition into osteoblast-like cells and calcification of extracellular matrix. Plasma samples collected from patients after the administration of activated vitamin D3 caused significantly increased ALP activity in SMC compared to the samples drawn prior to activated vitamin D3 and here, again induction of ferritin diminished the osteoblastic transformation. Our data suggests that pharmacological induction of ferritin prevents osteoblastic transformation of SMC. Hence, utilization of such agents that will cause enhanced ferritin synthesis may have important clinical applications in prevention of vascular calcification.

Animal Models to Study Links between Cardiovascular Disease and Renal Failure and Their Relevance to Human Pathology

The close association between cardiovascular pathology and renal dysfunction is well documented and significant. Patients with conventional risk factors for cardiovascular disease like diabetes and hypertension also suffer renal dysfunction. This is unsurprising if the kidney is simply regarded as a “modified blood vessel” and thus, traditional risk factors will affect both systems. Consistent with this, it is relatively easy to comprehend how patients with either sudden or gradual cardiac and or vascular compromise have changes in both renal hemodynamic and regulatory systems. However, patients with pure or primary renal dysfunction also have metabolic changes (e.g., oxidant stress, inflammation, nitric oxide, or endocrine changes) that affect the cardiovascular system. Thus, cardiovascular and renal systems are intimately, bidirectionally and inextricably linked. Whilst we understand several of these links, some of the mechanisms for these connections remain incompletely explained. Animal models of cardiovascular and renal disease allow us to explore such mechanisms, and more importantly, potential therapeutic strategies. In this article, we review various experimental models used, and examine critically how representative they are of the human condition.

Calcium Disorders in the Emergency Department: Independent Risk Factors for Mortality

Background

Calcium disorders are common in both intensive care units and in patients with chronic kidney disease and are associated with increased morbidity and mortality. It is unknown whether calcium abnormalities in unselected emergency department admissions have an impact on in-hospital mortality.

Methods

This cross-sectional analysis included all admissions to the Emergency Department at the Inselspital Bern, Switzerland from 2010 to 2011. For hyper- and hypocalcaemic patients with a Mann-Whitney U-test, the differences between subgroups divided by age, length of hospital stay, creatinine, sodium, chloride, phosphate, potassium and magnesium were compared. Associations between calcium disorders and 28-day in-hospital mortality were assessed using the Cox proportional hazard regression model.

Results

8,270 patients with calcium measurements were included in our study. Overall 264 (3.2%) patients died. 150 patients (6.13%) with hypocalcaemia and 7 patients with hypercalcaemia (6.19%) died, in contrast to 104 normocalcaemic patients (1.82%). In univariate analysis, calcium serum levels were associated with sex, mortality and pre-existing diuretic therapy (all p<0.05). In multivariate Cox regression analysis, hypocalcaemia and hypercalcaemia were independent risk factors for mortality (HR 2.00 and HR 1.88, respectively; both p<0.01).

Conclusion

Both hypocalcaemia and hypercalcaemia are associated with increased 28-day in-hospital mortality in unselected emergency department admissions.