Treatment effects of renin-angiotensin aldosterone system blockade on kidney failure and mortality in chronic kidney disease patients

Association of Renal Impairment with Clinical Outcomes Following Endovascular Therapy in Acute Basilar Artery Occlusion

Purpose

Renal impairment (RI) is associated with unfavourable outcome after acute ischaemic stroke with anterior circulation large vessel occlusion. We assessed the association of RI with clinical outcomes in patients with acute basilar artery occlusion (ABAO), and the impact of RI on the effects of endovascular therapy (EVT) versus standard medical treatment (SMT).

Patients and Methods

We used data from the BASILAR registry, an observational, prospective, nationwide study of patients with ABAO in routine clinical practice in China. Baseline estimated glomerular filtration rate (eGFR) was recorded at admission. The primary outcome was the modified Rankin Scale (mRS) score at 90 days. Secondary outcomes included favourable outcome (mRS score 0-3), mortality, and symptomatic intracranial haemorrhage (sICH). Multivariate logistic regression was used to assess the association of RI with mortality and functional improvement at 90 days.

Results

Among 829 patients enrolled, 747 patients were analysed. The median baseline eGFR was 89 mL/min/1.73m2 (IQR, 71-100), and 350 (46.8%), 297 (39.8%), and 100 (13.4%) patients had baseline eGFR values of ≥90, 60-89, and <60 mL/min/1.73m2, respectively. RI was associated with increased mortality (adjusted odds ratio [aOR], 1.97; 95% CI, 1.15-3.67) at 90 days and decreased survival probability (aOR 1.74; 95% CI, 1.30-2.33) within 1 year. EVT was associated with better functional improvement (common aOR, 2.50; 95% CI, 1.43-4.35), favourable outcome (aOR 5.42; 95% CI, 1.92-15.29) and lower mortality (aOR 0.47; 95% CI, 0.25-0.88) in ABAO patients with eGFR ≥90 mL/min/1.73m2. However, RI was not modified the relationship of EVT with functional improvement (common aOR, 3.03; 95% CI, 0.81-11.11), favourable outcome (aOR 2.10; 95% CI, 0.45-9.79), and mortality (aOR 0.56; 95% CI, 0.15-2.06) by eGFR categories.

Conclusion

RI is associated with reduced efficacy of EVT and worse functional outcome and higher mortality at 3 months and lower survival probability at 1 year in patients with ABAO.

Sacubitril/valsartan: research progress of multi-channel therapy for cardiorenal syndrome

Cardiorenal syndrome (CRS) results from complex interaction between heart and kidneys, inducing simultaneous acute or chronic dysfunction of these organs. Although its incidence rate is increasing with higher mortality in patients, effective clinical treatment drugs are currently not available. The literature suggests that renin-angiotensin-aldosterone system (RAAS) and diuretic natriuretic peptide (NP) system run through CRS. Drugs only targeting the RAAS and NPs systems are not effective. Sacubitril/valsartan contains two agents (sacubitril and valsartan) that can regulate RAAS and NPs simultaneously. In the 2017 American College of Cardiology/American Heart Association/American Heart Failure (HF) ssociation (ACC/AHA/HFSA) guideline, sacubitril/valsartan was recommended as standard therapy for HF patients. The latest research shows that Combined levosimendan and Sacubitril/Valsartan markets are protected the heart and kidney against cardiovascular syndrome in rat. However, fewer studies have reported its therapeutic efficacy in CRS treatment, and their results are inconclusive. Therefore, based on RAAS and NPs as CRS biomarkers, this paper summarizes possible pathophysiological mechanisms and preliminary clinical application effects of sacubitril/valsartan in the prevention and treatment of CRS. This will provide a pharmacological justification for expanding sacubitril/valsartan use to the treatment of CRS.

New eGFR equations: Implications for cardiologists and racial inequities

Recently, a new equation to predict estimated glomerular filtration rate (eGFR) that does not include a variable for race has been endorsed by professional organizations and increasingly adopted by clinical laboratories. We discuss the reasoning behind the development of the new equation, implications for cardiologists, and how the new eGFR equation could impact disparities in the cardiovascular care of these patients. Race, a social construct, is a poor proxy for biological variability. Clinical trials which recruit underrepresented minorities and advances in genomic medicine could accelerate the development of personalized medicine and help decrease inequalities in clinical outcomes.

Supply/demand ratio for medical consultations, diagnostic tests and chronic kidney disease monitoring in the Brazilian National Health System: a descriptive study, state of São Paulo, Brazil, 2019

OBJECTIVE

To determine the supply/demand ratio for procedures related to diagnosis and treatment for chronic kidney disease in the Brazilian National Health System (SUS), in the state of São Paulo, Brazil, 2019.

METHODS

This was a descriptive study, using data from the SUS outpatient and hospital information systems. The numbers of medical consultations, diagnostic and chronic kidney disease monitoring tests, performed in the period, were compared with the demand estimation, obtained through ministerial guidelines.

RESULTS

Exclusive SUS users were 28,791,244, and individuals with arterial hypertension and/or diabetes mellitus, 5,176,188. The number of procedures performed and the ratio between this number and the needs of the population were 389,414 consultations with nephrologists (85%); 11,540,371 serum creatinine tests (223%); 705,709 proteinuria tests (14%); 438,123 kidney ultrasounds (190%); and 1,045 kidney biopsies (36%).

CONCLUSION

In the chronic kidney disease care in the SUS it could be seen simultaneous existence of lack of supply, waste and inadequate screening of important procedures.

The Effect of FGF23 on Cardiac Hypertrophy Is Not Mediated by Systemic Renin-Angiotensin- Aldosterone System in Hemodialysis

Fibroblast growth factor 23 (FGF23) is elevated in patients with chronic kidney disease and contributes to left ventricular hypertrophy (LVH). The aim of the analysis was to determine whether this effect is mediated by the renin-angiotensin-aldosterone system (RAAS) in hemodialysis. Serum samples from 62 randomized hemodialysis patients with LVH were analyzed for plasma renin activity (PRA-S), angiotensin II (AngII), and metabolites, angiotensin-converting enzyme-2 (ACE2) and aldosterone using a high throughput mass spectrometry assay. Compared to healthy individuals, levels of the RAAS parameters PRA-S, AngII and aldosterone were generally lower [median (IQR) PRA-S 130 (46–269) vs. 196 (98, 238) pmol/L; AngII 70 (28–157) vs. 137 (76, 201) pmol/L; Aldosterone 130 (54, 278) vs. 196 (98, 238) pmol/L]. We did not find an indication that the effect of FGF23 on LVH was mediated by RAAS parameters, with all estimated indirect effects virtually zero. Furthermore, FGF23 was not associated with RAAS parameter levels throughout the study. While there was a clear association between FGF23 levels and left ventricular mass index (LVMI) at the end of the study and in the FGF23 fold change and LVMI change analysis, no association between RAAS and LVMI was observed. Serum concentrations of PRA-S, AngII, and aldosterone were below the ranges measured in healthy controls suggesting that RAAS is not systemically activated in hemodialysis patients. The effect of FGF23 on LVMI was not mediated by systemic RAAS activity. These findings challenge the current paradigm of LVH progression and treatment with RAAS blockers in dialysis.

Renoprotective Roles of Curcumin

The use of herb-based therapies is increasing over the past decades. These agents have been reported to provide many beneficial effects in many experimental and clinical studies. Curcumin is one of these agents which has potent pharmacological effects enabling it for the prevent and treatment of many diseases and pathologies such as renal disorders, hyperglycemia, oxidative stress, hypertension, and dyslipidemia. However, the exact molecular mechanisms mediating these renoprotective effects of curcumin are not well established. So, in the current study, we surveyed for possible renoprotective roles of curcumin and concluded how curcumin protects against renal injuries.

Effect of angiotensin II receptor blocker therapy on markers of fibrosis and immune inflammation in hypertensive patients with chronic kidney disease after ischemic stroke

Aim. To compare the effect of angiotensin II receptor blocker therapy (azilsartan, telmisartan) on fibrosis and immune inflammation markers in hypertensive patients with chronic kidney disease (CKD) after ischemic stroke (IS).

Material and methods. The study included 76 hypertensive patients aged 60-74 years (mean age, 66±5 years) with CKD after IS. Patients were randomly divided into following pharmacotherapy groups: 38 patients — telmisartan group; 36 patients — azilsartan group. The control group consisted of 20 hypertensive people (mean age, 63±2 years) without a history of CKD and IS. The levels of matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were determined by enzyme-linked immunosorbent assay (ELISA Kit, USA). The levels of interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), interferon γ (INF-γ), monocytic chemoattractant protein 1 (MCP-1) were assessed using Vector-Best kit (Russia).

Results. Six-month azilsartan therapy led to a decrease in the levels of MMP-9 by 19,9% (p<0,01), TIMP-1 by 7,5% (p<0,05), IL-1β by 7,8%, TNF-α by 13,5%, INF-γ by 7,1%, MCP-1 by 13% (p<0,05). Telmisartan therapy was associated with a decrease in the levels of MMP-9 by 39,1% (p<0,01), TIMP-1 by 16,4%, IL-1β by 10,1% (p<0,05), TNF-α by 20,8% (p<0,01), INF-γ by 14,6% (p<0,05), MCP-1 by 21,3% (p<0,01). Intergroup comparison revealed more pronounced changes in the levels of MMP-9 by 19,2% (p<0,01), TIMP-1 by 7,2% (p<0,05), TNF-α by 7,3% (p<0,05), INF-γ by 7,5% (p<0,05), and MCP-1 by 8,3% (p<0,05) when using telmisartan compared to azilsartan. When using telmisartan, the increase in glomerular filtration rate (GFR) was 14,2% (p<0,05) higher compared to azilsartan.

Conclusion. Six-month telmisartan therapy in hypertensive patients with CKD after stroke was accompanied by a more pronounced decrease in markers of myocardial fibrosis (MMP-9, TIMP-1) and immune inflammation (TNF-α, INF-γ, MCP-1) compared with azilsartan, as well as with more pronounced improvement in renal function.

Impact of Novel Guidelines on Multifactorial Control and Its Association with Mortality in Adult Patients with Hypertension and Newly Diagnosed Type 2 Diabetes: A 4-Year Prospective Multicenter Study

METHODS

This prospective, observational study involved adult hypertensive patients with newly diagnosed type 2 diabetes mellitus at two university hospitals in Vietnam. The median time of follow-up was 4 years (August 2016-August 2020). The primary outcome was time to all-cause mortality.

RESULTS

246 patients were included with a mean age of 64.5 ± 10.4. 58.5% were females. 64.2% were categorized as high risk. At baseline, ischemic heart disease, dyslipidemia, and chronic kidney disease (CKD) were present in 54.9%, 67.1%, and 41.1% of patients. Renin-angiotensin-aldosterone inhibitor, metformin, and statin were prescribed in 89.8%, 66.3%, and 67.1%. Among three risk factors, LDL-c control was the hardest to achieve, increasing from 5.7% to 8.5%. In contrast, blood pressure control decreased from 56.1% in 2016 to 30.2% in 2020, when the second wave of COVID-19 hit our nation. While contemporary targets resulted in persistently low simultaneous control at 1.2%, significant improvement was observed with conventional criteria (blood pressure  < 140/90 mmHg, HbA1c < 7%, LDL-c < 70 mg/dl), increasing from 14.6% to 33.7%. During follow-up, the mortality rate was 24.4 events per 1000 patient-years, exclusively in patients with early newly diagnosed diabetes. Improving control overtime, not at baseline, was associated with less mortality. Conversely, age >75 years (HR = 2.6) and CKD (HR = 4.9) were associated with increased mortality.

CONCLUSION

These findings demonstrated real-world difficulties in managing hypertension and newly diagnosed diabetes, especially with stringent criteria from novel guidelines. High-risk profile, high mortality, and poor simultaneous control warrant more aggressive cardiorenal protection, focusing more on aging CKD patients with early newly diagnosed diabetes.

Sacubitril/valsartan in chronic kidney disease: From pharmacological mechanism to clinical application

Chronic kidney disease (CKD) is an irreversible, progressive disease characterized by persistent kidney damage, and significantly increased risks of cardiovascular event. However, therapeutic strategies to prevent or slow the progression of CKD remain limited. Sacubitril/valsartan (LCZ696), the representative of the first novel angiotensin receptor-neprilysin inhibitor, has been incorporated into clinical practice guidelines for improving outcomes as a milestone in patients with heart failure. Considering the complex and close relationship between CKD and heart failure, LCZ696 may be beneficial in the treatment of CKD. This review summarizes the pharmacological mechanism and clinical application of LCZ696 in patients with CKD, including its effect on cardiovascular risk and renal outcome, together with potential adverse events. Additionally, due to the influence of serum creatinine and estimated glomerular filtration rate on LCZ696 in patients with heart failure, we also discussed the effects of LCZ696 in patients with advanced CKD and end-stage renal disease. It should be noted that, current clinical studies on LCZ696 are mostly carried out in patients with heart failure, and renal indicators are selected as secondary outcomes. Therefore, more researches should be conducted in patients with CKD alone in the future, to determine the efficacy and safety of LCZ696 in patients with CKD.

New Pandemic: Obesity and Associated Nephropathy

Incidence of obesity related renal disorders have increased 10-folds in recent years. One of the consequences of obesity is an increased glomerular filtration rate (GFR) that leads to the enlargement of the renal glomerulus, i.e., glomerulomegaly. This heightened hyper-filtration in the setting of type 2 diabetes irreparably damages the kidney and leads to progression of end stage renal disease (ESRD). The patients suffering from type 2 diabetes have progressive proteinuria, and eventually one third of them develop chronic kidney disease (CKD) and ESRD. For ameliorating the progression of CKD, inhibitors of renin angiotensin aldosterone system (RAAS) seemed to be effective, but on a short-term basis only. Long term and stable treatment strategies like weight loss via restricted or hypo-caloric diet or bariatric surgery have yielded better promising results in terms of amelioration of proteinuria and maintenance of normal GFR. Body mass index (BMI) is considered as a traditional marker for the onset of obesity, but apparently, it is not a reliable indicator, and thus there is a need for more precise evaluation of regional fat distribution and amount of muscle mass. With respect to the pathogenesis, recent investigations have suggested perturbation in fatty acid and cholesterol metabolism as the critical mediators in ectopic renal lipid accumulation associated with inflammation, increased generation of ROS, RAAS activation and consequential tubulo-interstitial injury. This review summarizes the renewed approaches for the obesity assessment and evaluation of the pathogenesis of CKD, altered renal hemodynamics and potential therapeutic targets.

The Non-Steroidal Mineralocorticoid Receptor Antagonist KBP-5074 Limits Albuminuria and has Improved Therapeutic Index Compared With Eplerenone in a Rat Model With Mineralocorticoid-Induced Renal Injury

The therapeutic indices (TIs) and efficacy of the non-steroidal mineralocorticoid receptor antagonist (MRA) KBP-5074 and steroidal MRA eplerenone were evaluated in a uninephrectomized Sprague Dawley rat model of aldosterone-mediated renal disease. In two parallel studies, rats were placed on a high-salt diet and received aldosterone by osmotic mini-pump infusion over the course of 27 days. The urinary albumin-to-creatinine ratio (UACR) was evaluated after 7, 14, and 26 days of treatment. Serum K⁺ was evaluated after 14 and 27 days of treatment. Urinary Na⁺, urinary K⁺, and urinary Na⁺/K⁺ ratio were evaluated after 7, 14, and 26 days of treatment. The TI was calculated for each drug as the ratio of the concentration of drug producing 50% of maximum effect (EC₅₀) for increasing serum K⁺ to the EC₅₀ for lowering UACR. The TIs were 24.5 for KBP-5074 and 0.620 for eplerenone, resulting in a 39-fold improved TI for KBP-5074 compared with eplerenone. Aldosterone treatment increased UACR, decreased serum K⁺, and decreased urinary Na⁺ relative to sham-operated controls that did not receive aldosterone infusion in both studies, validating the aldosterone/salt renal injury model. KBP-5074 prevented the increase in UACR at 0.5, 1.5, and 5 mg/kg BID while eplerenone did so only at the two highest doses of 50 and 450 mg/kg BID. Both KBP-5074 and eplerenone blunted the reduction in serum K⁺ seen in the aldosterone treatment group, with significant increases in serum K⁺ at the high doses only (5 mg/kg and 450 mg/kg BID, respectively). Additionally, the urinary Na⁺ and Na⁺/K⁺ ratio significantly increased at the middle and high doses of KBP-5074, but only at the highest dose of eplerenone. These results showed increased TI and efficacy for KBP-5074 compared with eplerenone over a wider therapeutic window.

Dojuksan ameliorates tubulointerstitial fibrosis through irisin-mediated muscle-kidney crosstalk

BACKGROUND

Sarcopenia progresses in chronic kidney disease (CKD) and is positively correlated with mortality in end-stage kidney disease patients. Circulating irisin, an exercise-induced myokine, gradually decreases during CKD stage progression. Irisin inhibits the progression of kidney fibrosis, which is the final common outcome of CKD. Our preliminary study with C2C12 cells showed that Dojuksan, a herbal decoction, increases the expression of PGC1α (a regulator of irisin) and FNDC5 (a precursor of irisin).

HYPOTHESIS

Dojuksan may increase circulating irisin and prevent the progression of kidney fibrosis.

STUDY DESIGN AND METHODS

Unilateral ureteral obstruction (UUO) was performed on seven-week-old male C57BL/6 mice to induce kidney tubulointerstitial fibrosis. Dojuksan (50, 100, or 200 mg/kg/day) or losartan (1.5 mg/kg/day), a standard clinical treatment for CKD, was administered orally one day prior to surgery and continued for seven days thereafter. To determine the role of irisin released from muscles, TGFβ-stimulated murine proximal tubular epithelial cells (mProx24 cells) were treated with conditioned media (CM) from Dojuksan-treated C2C12 muscle cells transfected with FNDC5 siRNA.

RESULTS

UUO mice exhibited muscle wasting along with progressive kidney injury. Similar to losartan, Dojuksan ameliorated kidney inflammation and fibrosis in UUO mice. Dojuksan, but not losartan, increased plasma irisin concentration in UUO mice. Dojuksan significantly increased basal FNDC5 expression and inhibited TNFα-induced and indoxyl sulfate-induced FNDC5 down-regulation in C2C12 cells. The TGFβ-induced collagen I (COL1) up-regulation in mProx24 cells was effectively inhibited by CM from C2C12 cells after Dojuksan treatment. Moreover, irisin inhibited TGFβ-induced COL1 in mProx24 cells, which was not affected by CM from C2C12 cells transfected with FNDC5 siRNA.

CONCLUSION

Dojuksan ameliorates kidney fibrosis through irisin-mediated muscle-kidney crosstalk, suggesting that Dojuksan may be used as an alternative therapeutic agent against CKD.

Liraglutide Improves Estimated Glomerular Filtration Rate Slopes in Patients with Chronic Kidney Disease and Type 2 Diabetes: A 7-Year Retrospective Analysis

Background: Liraglutide was administered to patients with type 2 diabetes, and its effects on estimated glomerular filtration rate (eGFR) slopes and albuminuria were retrospectively evaluated. Methods: This study included 568 patients with type 2 diabetes who received liraglutide therapy (up to 0.9 mg/day) >1 year and were followed-up for a maximum of 2 years before and 7 years after treatment. The decline in renal function was estimated as the slope of the individual linear regression line of eGFR over the follow-up time. Spot urine samples were collected to measure albuminuria, which were calculated using creatinine levels. In addition, HbA1c, body weight, blood pressure, and heart rate were monitored. Results: The mean liraglutide treatment period was 3.1 ± 2.0 years. The mean baseline eGFR slope [mL/(min ·1.73 m²·year)] was -2.75 ± 6.04. After liraglutide treatment, the mean eGFR slope significantly improved (-1.42 ± 4.30, P < 0.01). This effect appeared more pronounced for baseline eGFRs <45 mL/(min ·1.73 m²). Albuminuria, HbA1c, body weight, and systolic blood pressure levels were significantly reduced after treatment with liraglutide for 1 year, whereas diastolic blood pressure and heart rates were increased. Conclusions: Patients treated with liraglutide experienced a significantly slower annual decline in kidney function. The benefit appeared more pronounced in patients with the development and progression of diabetic kidney disease. These results suggest that the benefits of liraglutide on kidney function identified in clinical trials appear to be well generalizable to clinical practice.

Longer Predialysis ACEi/ARB Utilization Is Associated With Reduced Postdialysis Mortality

BACKGROUND

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ACEi/ARB) improve predialysis outcomes; however, ACEi/ARB are underused in patients transitioning to dialysis. We examined the association of different patterns of predialysis ACEi/ARB use with postdialysis survival and whether potentially modifiable adverse events are associated with lower predialysis ACEi/ARB use.

METHODS

This was a historic cohort study of 34,676 US veterans with, and 10,690 without, ACEi/ARB exposure in the 3-year predialysis period who subsequently transitioned to dialysis between 2007 and 2014. Associations of different patterns of predialysis ACEi/ARB use with postdialysis all-cause mortality and with predialysis acute kidney injury and hyperkalemia events were examined using multivariable adjusted regression analyses.

RESULTS

The mean age of the cohort was 70 years, 98% were males and 27% were African Americans. Compared to ACEi/ARB nonuse, continuous ACEi/ARB use was associated with lower postdialysis all-cause mortality (adjusted hazard ratio [aHR]; 95% confidence interval [95% CI] 0.87; 0.83-0.92). In analyses modeling the duration of predialysis ACEi/ARB use, ACEi/ARB use of 50%-74% and ≥75% were associated with lower mortality compared to nonuse (adjusted hazard ratio, 95% confidence interval 0.96, 0.92-0.99 and 0.91; 0.88-0.94, respectively), whereas no increase in postdialysis survival was observed with shorter predialysis ACEi/ARB use. Predialysis acute kidney injury was associated with shorter duration (<50%) of ACEi/ARB use and hyperkalemia was associated with interrupted and ACEi/ARB use of <75%.

CONCLUSIONS

Longer predialysis ACEi/ARB exposure was associated with lower postdialysis mortality. Prospective studies are needed to evaluate the benefits of strategies enabling uninterrupted predialysis ACEi/ARB use.

Add-On Therapy with DPP-4 Inhibitors May Improve Renal Function Decline in α-Glucosidase Inhibitor and Metformin Users: A Retrospective Observational Study

PURPOSE

We retrospectively evaluated the long-term effect of dipeptidyl peptidase (DPP)-4 inhibitors on estimated glomerular filtration rate (eGFR) slopes, and then evaluated the beneficial interaction between DPP-4 inhibitor initiation and baseline use of α-glucosidase inhibitor and/or metformin in patients with diabetic kidney disease.

PATIENTS AND METHODS

Altogether, 1512 patients with type 2 diabetes were receiving DPP-4 inhibitor therapy over 1 year and were followed up for a maximum of 2 years before and after 7 years of treatment. The decline in renal function was estimated as the slope of the individual linear regression line of eGFR over 2-year follow-up. Prescription data on medications before and after DPP-4 inhibitor treatment were examined.

RESULTS

The mean length of DPP-4 inhibitor treatment was 5.3 ± 2.6 years. The baseline mean eGFR slope (mL/min/1.73m²/year) was -2.24 ± 6.05. After DPP-4 inhibitor treatment, mean eGFR slope was significantly improved (-1.53 ± 6.36, P < 0.01) in patients with type 2 diabetes. This effect appeared more pronounced for baseline use of α-glucosidase inhibitor and/or metformin in patients with diabetic kidney disease. These non-users showed a trend towards attenuation or no effects.

CONCLUSION

In the present study, patients treated with DPP-4 inhibitors had a significantly slower annual loss of kidney function. The benefit appears pronounced in α-glucosidase inhibitor and metformin users with advanced renal dysfunction. These results suggest that the beneficial effects of DPP-4 inhibitors on kidney function may have occurred in the presence of an α-glucosidase inhibitor and/or metformin.

Chronic kidney disease in the pathogenesis of acute ischemic stroke

Chronic kidney disease has a graded and independent inverse impact on cerebrovascular health. Both thrombotic and hemorrhagic complications are highly prevalent in chronic kidney disease patients. Growing evidence suggests that in chronic kidney disease patients, ischemic strokes are more common than hemorrhagic strokes. Chronic kidney disease is asymptomatic until an advanced stage, but mild to moderate chronic kidney disease incites various pathogenic mechanisms such as inflammation, oxidative stress, neurohormonal imbalance, formation of uremic toxins and vascular calcification which damage the endothelium and blood vessels. Cognitive dysfunction, dementia, transient infarcts, and white matter lesions are widespread in mild to moderate chronic kidney disease patients. Uremic toxins produced after chronic kidney disease can pass through the blood-brain barrier and mediate cognitive dysfunction and neurodegeneration. Furthermore, chronic kidney disease precipitates vascular risk factors that can lead to atherosclerosis, hypertension, atrial fibrillation, and diabetes. Chronic kidney disease also exacerbates stroke pathogenesis, worsens recovery outcomes, and limits the eligibility of stroke patients to receive available stroke therapeutics. This review highlights the mechanisms involved in the advancement of chronic kidney disease and its possible association with stroke.

Xanthine Oxidase Inhibitor Febuxostat Exerts an Anti-Inflammatory Action and Protects against Diabetic Nephropathy Development in KK-Ay Obese Diabetic Mice

Hyperuricemia has been recognized as a risk factor for insulin resistance as well as one of the factors leading to diabetic kidney disease (DKD). Since DKD is the most common cause of end-stage renal disease, we investigated whether febuxostat, a xanthine oxidase (XO) inhibitor, exerts a protective effect against the development of DKD. We used KK-Ay mice, an established obese diabetic rodent model. Eight-week-old KK-Ay mice were provided drinking water with or without febuxostat (15 μg/mL) for 12 weeks and then subjected to experimentation. Urine albumin secretion and degrees of glomerular injury judged by microscopic observations were markedly higher in KK-Ay than in control lean mice. These elevations were significantly normalized by febuxostat treatment. On the other hand, body weights and high serum glucose concentrations and glycated albumin levels of KK-Ay mice were not affected by febuxostat treatment, despite glucose tolerance and insulin tolerance tests having revealed febuxostat significantly improved insulin sensitivity and glucose tolerance. Interestingly, the IL-1β, IL-6, MCP-1, and ICAM-1 mRNA levels, which were increased in KK-Ay mouse kidneys as compared with normal controls, were suppressed by febuxostat administration. These data indicate a protective effect of XO inhibitors against the development of DKD, and the underlying mechanism likely involves inflammation suppression which is independent of hyperglycemia amelioration.

GLP-1 Receptor Agonists and Kidney Protection

Type 2 diabetes mellitus (T2DM) is the leading cause of chronic kidney disease (CKD). Diabetic nephropathy (DN) is determined by specific pathological structural and functional alterations of the kidneys in patients with diabetes, and its clinical manifestations are albuminuria and decline of glomerular filtration rate (GFR). Apart from renin–angiotensin–aldosterone system (RAAS) inhibitors, no other drugs are currently available as therapy for diabetic kidney disease (DKD). Glucagon-like peptide-1 receptor (GLP-1R) agonists are a new class of anti-hyperglycemic drugs which have been demonstrated to prevent the onset of macroalbuminuria and reduce the decline of GFR in diabetic patients. These drugs may exert their beneficial actions on the kidneys through blood glucose- and blood pressure (BP)-lowering effects, reduction of insulin levels and weight loss. Clinical benefits of GLP-1R agonists were acknowledged due to data from large randomized phase III clinical trials conducted to assess their cardiovascular(CV) safety. These drugs improved renal biomarkers in placebo-controlled clinical studies, with effects supposed to be independent of the actions on glycemic control. In this review, we will focus on the actions of GLP-1R agonists on glucose metabolism and kidney physiology, and evaluate direct and indirect mechanisms through which these drugs may confer renal protection.

The Xanthine Oxidase Inhibitor Febuxostat Suppresses the Progression of IgA Nephropathy, Possibly via Its Anti-Inflammatory and Anti-Fibrotic Effects in the gddY Mouse Model

Recent clinical studies have demonstrated the protective effect of xanthine oxidase (XO) inhibitors against chronic kidney diseases, although the underlying molecular mechanisms remain unclear. However, to date, neither clinical nor basic research has been carried out to elucidate the efficacy of XO inhibitor administration for IgA nephropathy. We thus investigated whether febuxostat, an XO inhibitor, exerts a protective effect against the development of IgA nephropathy, using gddY mice as an IgA nephropathy rodent model. Eight-week-old gddY mice were provided drinking water with (15 μg/mL) or without febuxostat for nine weeks and then subjected to experimentation. Elevated serum creatinine and degrees of glomerular sclerosis and fibrosis, judged by microscopic observations, were significantly milder in the febuxostat-treated than in the untreated gddY mice, while body weights and serum IgA concentrations did not differ between the two groups. In addition, elevated mRNA levels of inflammatory cytokines such as TNFα, MCP-1, IL-1β, and IL-6, collagen isoforms and chemokines in the gddY mouse kidneys were clearly normalized by the administration of febuxostat. These data suggest a protective effect of XO inhibitors against the development of IgA nephropathy, possibly via suppression of inflammation and its resultant fibrotic changes, without affecting the serum IgA concentration.

Cost-Effectiveness Analysis of Renin-Angiotensin Aldosterone System Blockade in Progression of Chronic Kidney Disease

OBJECTIVES

To assess the cost effectiveness of renin-angiotensin aldosterone system (RAAS) blockade in the progression of chronic kidney disease using Thai clinical data in 2014.

METHODS

A Markov model for cost-effectiveness analysis was applied to estimate from a societal perspective the cost per quality-adjusted life-year (QALY) gained and the incremental cost-effectiveness ratio of RAAS versus non-RAAS used in preventing the progression of end-stage renal disease and death stratified by diabetic and nondiabetic patients. Input parameters related to clinical outcomes were obtained from a cohort study of treatment effectiveness, whereas costs were retrieved from the Ramathibodi Hospital electronic database in 2015 and the Health Intervention and Technology Assessment Program in Thailand. One-way analysis and probabilistic sensitivity analysis were performed to evaluate uncertainty surrounding model parameters.

RESULTS

From the model, using RAAS improved QALY from 2.41 to 3.16 years and from 2.37 to 3.20 years in diabetic and nondiabetic groups, respectively. The incremental cost-effectiveness ratios for these groups were 78,250 baht (US $2,353.39) and 66,674 baht (US $2,005.22), respectively.

CONCLUSIONS

Using RAAS in patients with chronic kidney disease improved QALY in both diabetic and nondiabetic patients and proved to be cost-effective.