Chronic kidney disease in the general population

The Awareness, Prevalence, and Risk Factors of Chronic Kidney Disease Among Diabetes Mellitus and Hypertensive Patients in the Aseer Region, Saudi Arabia

Background and objective Given its ever-increasing burden, chronic kidney disease (CKD) represents a significant public health threat. CKD is characterized by a gradual alteration in the kidney's normal glomerular filtration rate, which results in the progressive loss of kidney function over a period of time ranging from a few months to years. Diabetes mellitus (DM) and hypertension (HTN) are well-known risk factors for developing CKD and end-stage renal failure. In light of this, this study aimed to assess the awareness, prevalence, and risk factors of CKD in patients with diabetes and those with HTN in the Aseer region, the Kingdom of Saudi Arabia. Methods A correlational cross-sectional study was conducted among a sample of people across Saudi Arabia. The data collection was conducted via an online questionnaire circulated on social media platforms. The study questionnaire included socioeconomic and demographic information and medical history of DM, HTN, and CKD. Also, patients' awareness of and attitude towards CKD were assessed. Results A total of 301 diabetic or hypertensive patients fulfilling the inclusion criteria completed the study questionnaire. Of them, 174 (57.8%) were aged less than 55 years, while 127 (42.2%) were aged more than 55 years; 200 (66.4%) patients were males. A total of 94 (31.2%) study patients were diabetic, 64 (21.3%) were hypertensive, and 143 (47.5%) were both diabetic and hypertensive; 226 (75.1%) study patients had an overall good awareness of CKD while only 75 (24.9%) showed a poor awareness level. Higher awareness was associated with patients' age, education, and having CKD, DM, or HTN (p<0.05). Conclusion Our findings revealed that CKD was not common among study patients, and its prevalence was found to be less than estimated based on many studies in the literature. Also, diabetic and hypertensive patients showed a higher than satisfactory level of awareness of CKD, especially young patients with high levels of education.

Visualizing increased uptake of [18F]FDG and [18F]FTHA in kidneys from obese high-fat diet fed C57BL/6J mice using PET/CT ex vivo

It is known that high-fat diet (HFD) and/or diabetes may influence substrate preferences and energy demands in the heart preceding diabetic cardiomyopathy. They may also induce structural glomerular changes causing diabetic nephropathy. PET/CT has been utilized to examine uptake of energy substrates, and to study metabolic changes or shifts before onset of metabolic disorders. However, conventional PET/CT scanning of organs with relatively low uptake, such as the kidney, in small animals in vivo may render technical difficulties. To address this issue, we developed a PET/CT ex vivo protocol with radiolabeled glucose and fatty acid analouges, [18F]FDG and [18F]FTHA,to study substrate uptake in mouse kidneys. We also aimed to detect a possible energy substrate shift before onset of diabetic nephropathy. The ex vivo protocol reduced interfering background as well as interindividual variances. We found increased uptake of [18F]FDG and [18F]FTHA in kidneys after HFD, compared to kidneys from young mice on standard chow. Levels of kidney triglycerides also increased on HFD. Lipoprotein lipase (LPL) activity, the enzyme responsible for release of fatty acids from circulating lipoproteins, is normally increased in postprandial mice kidneys. After long-term HFD, we found that LPL activity was suppressed, and could therefore not explain the increased levels of stored triglycerides. Suppressed LPL activity was associated with increased expression of angiopoietin-like protein4, an inhibitor of LPL. HFD did not alter the transcriptional control of some common glucose and fatty acid transporters that may mediate uptake of [18F]FDG and [18F]FTHA. Performing PET/CT ex vivo reduced interfering background and interindividual variances. Obesity and insulin resistance induced by HFD increased the uptake of [18F]FDG and [18F]FTHA and triglyceride accumulation in mouse kidneys. Increased levels of [18F]FDG and [18F]FTHA in obese insulin resistant mice could be used clinically as an indicator of poor metabolic control, and a complementary test for incipient diabetic nephropathy.

Interaction between the stage of chronic kidney disease and diabetes mellitus as factors associated with mortality in chronic kidney disease patients: An external cohort study

INTRODUCTION

Diabetic kidney disease is the main cause of chronic kidney disease (CKD) worldwide. Both CKD and diabetes mellitus (DMT2) are important risk factors for mortality. However, it is still unknown if the risk of death is modified by the simultaneous presence of these diseases.

OBJECTIVE

To evaluate the presence of an interaction between DMT2 and CKD for mortality in a representative population of a Latin American country.

METHODS

It is an analytical cohort study of patients with CKD, who were followed for 4 years (between 2004 and 2009). We calculated the incidence rate, progression, survival (using Kaplan-Meier curves), interaction (on the additive and multiplicative scales) and impact of the different stages of CKD in patients with and without DMT2 (using a cox proportional hazards model).

RESULTS

In this population of 5663 individuals, both DMT2 and CKD are risk factors for mortality (p<0.001). We found a statistically significant difference in mortality between individuals with and without DMT2, who also had CKD stages 3-4 -5 (Log-rank p=0.0076). Additionally, we found a statistically significant interaction for mortality in both the additive and multiplicative scales between DMT2 and CKD (p=0.005). DMT2 was found to be a risk factor for mortality (Hazard Ratio 1.61 p<0.001), but in individuals with DMT2, the only risks significantly associated with mortality, were age, dyslipidemia and nephroprotective drugs. CONCLUSIóN: The interaction between CKD and DMT2 negatively modifies the risk of death of both diseases. This means that when the two diseases are present, the risk of mortality is lower than expected.

Mitochondrial Dysfunction in Individuals with Diabetic Kidney Disease: A Systematic Review

Mitochondrial dysfunction is implicated in the pathogenesis of diabetic kidney disease (DKD). Compared to the vast body of evidence from preclinical in vitro and in vivo studies, evidence from human studies is limited. In a comprehensive search of the published literature, findings from studies that reported evidence of mitochondrial dysfunction in individuals with DKD were examined. Three electronic databases (PubMed, Embase, and Scopus) were searched in March 2022. A total of 1339 articles were identified, and 22 articles met the inclusion criteria. Compared to non-diabetic controls (NDC) and/or individuals with diabetes but without kidney disease (DC), individuals with DKD (age ~55 years; diabetes duration ~15 years) had evidence of mitochondrial dysfunction. Individuals with DKD had evidence of disrupted mitochondrial dynamics (11 of 11 articles), uncoupling (2 of 2 articles), oxidative damage (8 of 8 articles), decreased mitochondrial respiratory capacity (1 of 1 article), decreased mtDNA content (5 of 6 articles), and decreased antioxidant capacity (3 of 4 articles) compared to ND and/or DC. Neither diabetes nor glycemic control explained these findings, but rather presence and severity of DKD may better reflect degree of mitochondrial dysfunction in this population. Future clinical studies should include individuals closer to diagnosis of diabetes to ascertain whether mitochondrial dysfunction is implicated in the development of, or is a consequence of, DKD.

Cardamomin protects from diabetes-induced kidney damage through modulating PI3K/AKT and JAK/STAT signaling pathways in rats

BACKGROUND

Diabetic nephropathy is one of the common complications of diabetes mellitus, which seriously affects the life quality and health of patients. In this study, we aimed to investigate the function of cardamonin (CAD) in diabetes-induced kidney damage in rats.

METHODS

The normal rat kidney tubular epithelial cells (NRK-52E) were pre-treated with different doses of CAD and then stimulated with methylglyoxal (MGO). Streptozotocin (STZ) induced diabetes rat model were received different doses of CAD treatment. MTT, EdU, Transwell, and flow cytometry was used to detect cell viability, proliferation, migration, and apoptosis. Western blot analysis was used to detect the expression of apoptosis related proteins, advanced glycation end-products (AGEs), receptor for AGEs (RAGE), epithelial mesenchymal transition (EMT) related proteins, phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway related proteins, and janus kinas/signal transducer and activator of transcription 3 (JAK/STAT3) related proteins. ELISA assay was used to detect the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β). The levels of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) were detected using commercial kit. Hematoxylin and eosin staining was used to assess pathological changes in rat kidney.

RESULTS

Compared with control group, MGO reduced cell viability and proliferation, enhanced migration and apoptosis of NRK-52E cells, while CAD inhibited these effects induced by MGO in NRK-52E cells. Moreover, CAD increased Bcl-2 expression and decreased the expression of Bax and cleaved caspase-3 in MGO-treated NRK-52E cells. Compared with control group, MGO increased the AGEs formation, the expression of RAGE and p-p65, the levels of TNF-α, IL-6, IL-1β, MDA in NRK-52E cells and reduced the levels of GSH and SOD, while treatment of CAD dose-dependently prevented these results. In addition, CAD attenuated MGO-induced EMT of MGO-treated NRK-52E cells. Mechanically, we identified that CAD repressed PI3K/AKT and JAK/STAT3 signaling in NRK-52E cells. Importantly, the kidney injury of diabetes rats was attenuated by CAD. Besides, STZ-induced inflammatory response, oxidative stress, and phosphorylation levels of PI3K, AKT, JAK2, and STAT3 were reduced by CAD in the rats.

CONCLUSION

CAD protects from diabetes-induced kidney damage through modulating PI3K/AKT and JAK/STAT signaling pathways in rats.

Interaction between the stage of chronic kidney disease and diabetes mellitus as factors associated with mortality in chronic kidney disease patients: An external cohort study

INTRODUCTION

Diabetic kidney disease is the main cause of chronic kidney disease (CKD) worldwide. Both CKD and diabetes mellitus (DMT2) are important risk factors for mortality. However, it is still unknown if the risk of death is modified by the simultaneous presence of these diseases.

OBJECTIVE

To evaluate the presence of an interaction between DMT2 and CKD for mortality in a representative population of a Latin American country.

METHODS

It is an analytical cohort study of patients with CKD, who were followed for 4 years (between 2004 and 2009). We calculated the incidence rate, progression, survival (using Kaplan-Meier curves), interaction (on the additive and multiplicative scales) and impact of the different stages of CKD in patients with and without DMT2 (using a cox proportional hazards model).

RESULTS

In this population of 5663 individuals, both DMT2 and CKD are risk factors for mortality (P < 0.001). We found a statistically significant difference in mortality between individuals with and without DMT2, who also had CKD stages 3 - 4 - 5 (Log-rank P = 0.0076). Additionally, we found a statistically significant interaction for mortality in both the additive and multiplicative scales between DMT2 and CKD (P = 0.005). DMT2 was found to be a risk factor for mortality (Hazard Ratio 1.61 P < 0.001), but in individuals with DMT2, the only risks significantly associated with mortality, were age, dyslipidemia and nephroprotective drugs. CONCLUSIóN: The interaction between CKD and DMT2 negatively modifies the risk of death of both diseases. This means that when the two diseases are present, the risk of mortality is lower than expected.

Prevalence of Subclinical Hypothyroidism in Chronic Kidney Disease in a Population-based Study: Tehran Thyroid Study

BACKGROUND

Chronic kidney disease (CKD) is a rising public health concern that has detrimental effects on cardiovascular health and overall survival. Subclinical hypothyroidism (SCH) has been associated with poor outcomes in the general population. It is thought to be more prevalent in CKD subjects, and their coexistence may contribute to poor outcomes in these patients. We aimed to determine the prevalence of SCH in CKD.

METHODS

Using data from the Tehran thyroid study, which is a prospective population-based cohort study, adult subjects with an estimated Glomerular Filtration Rate (eGFR) of 60 mL/min/1.73 m² or less were selected for studying the prevalence of thyroid abnormalities, as well as other known cardiovascular risk factors.

RESULTS

Of 5,626 subjects recruited, 823 (14.6%) individuals had CKD. Individuals with CKD were older, heavier, had a higher prevalence of diabetes, higher serum thyrotropin, and thyroid peroxidase anti-body levels, but lower free thyroxine levels. The prevalence of SCH was 7.3% and 5.2% (P < 0.001) in kidney disease and non-kidney disease subjects, respectively. However, there was no difference in the risk of SCH between CKD and non-CKD subjects after adjustment for age, sex, BMI, smoking, and TPOAb (OR: 1.28; 95%CI, 0.89 - 1.83). None of the metabolic markers compared between the CKD subgroups of those with and without SCH remained statistically significantly different after adjusting for age and gender.

CONCLUSIONS

The prevalence of SCH was not higher in CKD after controlling for confounding factors. Besides, CKD subjects with and without SCH had no different metabolic parameters.

An Interdisciplinary Approach to Optimize the Care of Transitioning Adolescents and Young Adults with CKD

Adolescents and young adults (AYAs) with CKD or end-stage kidney disease (ESKD) have unique medical, dental, psychosocial, neurocognitive, and academic needs and require close interdisciplinary collaboration to optimize their care. The etiology of CKD in AYAs is diverse compared to older adults. With their continuously improved survival, AYAs must start preparation for health-care transition (HCT) from pediatric- to adult-focused health care in the pediatric setting and it must continue at the adult-focused setting, given that their brain maturation and self-management skill acquisition occur until their mid-20s. While the growth and physical maturation of most visible body parts occur before 18 years of age, the prefrontal cortex of the brain, where reasoning, impulse control, and other higher executive functions reside, matures around 25 years of age. The HCT process must be monitored using patient- and caregiver-measuring tools to guide interventions. The HCT process becomes more complex when patients and/or caregivers have a language barrier, different cultural beliefs, or lower literacy levels. In this article, we discuss the unique comorbidities of pediatric-onset CKD/ESKD, provide information for a planned HCT preparation, and suggest interdisciplinary coordination as well as cultural and literacy-appropriate activities to achieve optimal patient outcomes.

Patterns of Toll-Like Receptor Expressions and Inflammatory Cytokine Levels and Their Implications in the Progress of Insulin Resistance and Diabetic Nephropathy in Type 2 Diabetic Patients

Background: Diabetic nephropathy (DNP) is a type 2 diabetes mellitus (T2DM) chronic complication, which is the largest single cause of end-stage kidney disease. There is an increasing evidence of the role of inflammation and Toll-like receptors (TLRs) as part of innate immune system in its development and progression. In addition, Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) downward signaling causes the production of proinflammatory cytokines, which can induce insulin (INS) resistance in T2DM.

Objective: The goal of this study was to estimate the expression of TLRs (TLR2 and TLR4) in relation to inflammation and INS resistance in nephrotic type 2 diabetic patients with or without renal failure and to discuss the role of these TLRs in DNP progression.

Patients and Methods: In this study, blood samples were obtained from type 2 diabetic patients with or without renal failure, and patients with non-diabetic renal failure were compared to healthy controls. All participants were tested for analysis of fasting plasma glucose and serum insulin, kidney function tests, C-reactive protein (CRP), and proinflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), and interleukin 6 (IL-6) as well as expression of TLR2 and TLR4 in peripheral blood (PB). Statistical analysis of data was done by using SPSS.

Results: Diabetic patients with renal failure exhibited significant increase in TLR2, TLR4 mRNA expression in PB in comparison with normal subjects, diabetic patients without renal failure and non-diabetic patients with renal failure. Both diabetic patients with or without kidney failure and non-diabetic patients with renal failure had increased TLR2 and TLR4 mRNA expression in association with increased levels of proinflammatory cytokines (TNF-α, IFN-γ, and IL-6) compared to normal subjects. The diabetic patients with kidney failure exhibited the highest elevation of TLRs, Th1 cytokines and CRP in association the highest record of insulin resistance.

Conclusion: Toll-like receptor 2 and Toll-like receptor 4 increased expression and Th2 cytokines may have an important role in the progression of DNP and deteriorations in insulin resistance in type 2 diabetic patients. Therefore, TLR2 and TLR4 may be a promising therapeutic target to prevent or retard DNP in type 2 diabetic patients.

Malignant fibrous histiocytoma amplified sequence 1 alleviates inflammation and renal fibrosis in diabetic nephropathy by inhibiting TLR4

BACKGROUND

Diabetic nephropathy (DN) is the most common complication of diabetes mellitus (DM). The signal pathway and molecular mechanism of renal fibrosis are not fully understood. In the present study, we aimed to explore the function of malignant fibrous histiocytoma amplified sequence 1 (MFHAS1) in DN.

METHOD

Mouse mesangial cells (MMCs) were treated with low glucose (LG) or high glucose (HG). TAK242 or short hairpin TLR4 (shTLR4) were employed to down-regulate Toll-like receptor 4 (TLR4). The effect of MFHAS1 knockdown or overexpression on fibrosis-related factors, inflammatory factors and TLR4 in MMCs were examined after transfecting with short hairpin RNA (shRNA) or MFHAS1 overexpressed plasmid, respectively. The expression levels of MFHAS1, inflammatory factors, fibrosis factors and TLR4 in db/db or streptozotocin (STZ) mice tissues and MMCs were examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. The effect of MFHAS1 overexpression in vivo was also evaluated.

RESULTS

The expression of MFHAS1 in db/db or STZ mice and HG-treated MMCs were significantly increased compared with normal control mice and LG-treated MMCs. Overexpression of MFHAS1 inhibited the expression of inflammatory and fibrotic factors, while knockdown of MFHAS1 promoted them. MFHAS1 suppressed the activation of TLR4 pathway via inhibiting the expression of TLR4, and then alleviating inflammation and fibrosis in DN. MFHAS1 overexpression in vivo improved the symptoms of STZ-induced DN mice.

CONCLUSION

The current study demonstrated that MFHAS1 relieved inflammation and renal fibrosis in DN mice via inhibiting TLR4. The results revealed that the MFHAS1 may be a molecular target in DN therapy.

Psychiatric comorbidity and quality of life in patients undergoing hemodialysis

Background

Hemodialysis has been shown to have an adverse impact on the emotional status of patients with end-stage renal disease (ESRD). Common associated psychological problems include depression, anxiety, fatigue, decreased quality of life, and an increased risk for suicide. This cross-sectional study aims to psychiatric assessment of ESRD patients on dialysis and patients’ quality of life (QOL). One hundred and seventeen patients with end-stage renal disease undergoing hemodialysis aged from 26 years to 77 years were enrolled from the Dialysis Unit at Shebin El Kom Teaching Hospital and Menoufia University Hospital and were approved by the local medical ethical committee. Cases were selected during the study period from October 2018 till May 2019. A semi-structured interview, clinical psychiatric assessment, psychometric test measuring psychiatric disorders, and psychometric test measuring QOL were measured.

Results

A reduction in scores of all domains of QOL was observed in ESRD patients with depression compared with patients without depression. There was a statistically significant correlation between QOL and presence of clinical illness either diabetes or hypertension among ESRD patients (P < 0.05). It was found that there was a reduction in all domains of QOL in patients with clinical illness compared with patients without.

Conclusions

Incidence of psychiatric illness among end-stage renal disease patients on hemodialysis is high. The most prevalent psychiatric disorders among these patients are depression and anxiety disorders. Poor quality of life (QOL) was also observed in ESRD patients.

AT1 and AT2 receptors modulate renal tubular cell necroptosis in angiotensin II-infused renal injury mice

Abnormal renin-angiotensin system (RAS) activation plays a critical role in the initiation and progression of chronic kidney disease (CKD) by directly mediating renal tubular cell apoptosis. Our previous study showed that necroptosis may play a more important role than apoptosis in mediating renal tubular cell loss in chronic renal injury rats, but the mechanism involved remains unknown. Here, we investigate whether blocking the angiotensin II type 1 receptor (AT1R) and/or angiotensin II type 2 receptor (AT2R) beneficially alleviates renal tubular cell necroptosis and chronic kidney injury. In an angiotensin II (Ang II)-induced renal injury mouse model, we found that blocking AT1R and AT2R effectively mitigates Ang II-induced increases in necroptotic tubular epithelial cell percentages, necroptosis-related RIP3 and MLKL protein expression, serum creatinine and blood urea nitrogen levels, and tubular damage scores. Furthermore, inhibition of AT1R and AT2R diminishes Ang II-induced necroptosis in HK-2 cells and the AT2 agonist CGP42112A increases the percentage of necroptotic HK-2 cells. In addition, the current study also demonstrates that Losartan and PD123319 effectively mitigated the Ang II-induced increases in Fas and FasL signaling molecule expression. Importantly, disruption of FasL significantly suppressed Ang II-induced increases in necroptotic HK-2 cell percentages, and necroptosis-related proteins. These results suggest that Fas and FasL, as subsequent signaling molecules of AT1R and AT2R, might involve in Ang II-induced necroptosis. Taken together, our results suggest that Ang II-induced necroptosis of renal tubular cell might be involved both AT1R and AT2R and the subsequent expression of Fas, FasL signaling. Thus, AT1R and AT2R might function as critical mediators.

Glucose and glycogen in the diabetic kidney: Heroes or villains?

Glucose metabolism in the kidney is currently foremost in the minds of nephrologists, diabetologists and researchers globally, as a result of the outstanding success of SGLT2 inhibitors in reducing renal and cardiovascular disease in individuals with diabetes. However, these exciting data have come with the puzzling but fascinating paradigm that many of the beneficial effects on the kidney and cardiovascular system seem to be independent of the systemic glucose lowering actions of these agents. This manuscript places into context an area of research highly relevant to renal glucose metabolism, that of glycogen accumulation and metabolism in the diabetic kidney. Whether the glycogen that abnormally accumulates is pathological (the villain), is somehow protective (the hero) or is inconsequential (the bystander) is a research question that may provide insight into the link between diabetes and diabetic kidney disease.

Angpt2 Induces Mesangial Cell Apoptosis through the MicroRNA-33-5p-SOCS5 Loop in Diabetic Nephropathy

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Mesangial cell (MC) loss is correlated with worsening renal function in DN. Disturbance of angiopoietin (Angpt)/Tie ligand-receptor system causes inflammation and abnormal angiogenesis. This association between elevated circulating Angpt2 and poor renal outcome has been in DN patients. However, the pathogenic role of Angpt2 in the MCs remains unknown. We found serum Angpt2 levels were elevated in type 2 diabetes mellitus (DM) patients and db/db mice, which correlated with albuminuria. Angpt2 synergistically induced MC apoptosis under high glucose (HG), and miR-33-5p regulated Angpt2-inducing MC apoptosis treated with HG. Loss of miR-33-5p increased suppressor of cytokine signaling 5 (SOCS5), leading to the inhibition of Janus kinase 1 and signal transducer and activator of transcription 3 signaling transduction. Elevated expression of SOCS5 was found in the MCs in kidney sections of both db/db mice and type 2 DM patients. Decreased miR-33-5p levels were found in the urine of db/db mice and type 2 DM patients, and miR-33-55p levels negatively correlated with albuminuria. Angpt2 leads to MC apoptosis via the miR-33-5p-SOCS5 loop in DN. miR-33-5p is predictive of kidney injury in DN. These findings may provide future applications in predicting renal dysfunction and the therapeutic potential of DN.

Stage progression and need for renal replacement therapy in a renal protection programme in Colombia. A cohort study

BACKGROUND

Due to the global burden represented by chronic kidney disease (CKD), the World Health Organization encouraged the implementation of renal protection programmes (RPP) to affect its incidence through prevention and control measures.

OBJECTIVES

To assess the effectiveness of a Colombian RPP in terms of its effect on the stage progression of CKD and the need for renal replacement therapy (RRT).

METHODS

An analytical study that monitored 2cohorts of patients diagnosed with CKD. The study compares the behaviour of clinical and renal impairment indicators from patients exposed to a RPP with that of patients following conventional treatment (CT). The population of both intervention groups was considered when determining the sample size. The incidence rate was calculated as well as patient survival (Kaplan Meier). In addition, a multivariate analysis (Cox) was used to calculate the influence that exposure to the RPP had on the outcomes of the patients following the RPP and those following CT.

RESULTS

The patients exposed to the RPP took longer to advance to the next CKD stage and require RRT. The incidence rate for progression is higher for the patients following CT (0.050, IC 95%: 0.040-0.064) compared to those in the RPP (0.034, IC 95%: 0.030-0.039). The ratio of incidence rates was 1.480 (IC 95% 1.21-1.90). The hazard of progression was lower for the RPP (HR: 0.855, IC 95%: 0.74- 0.98), as was the hazard of requiring RRT (HR: 0.797, IC 95%: 0.606-1.049).

CONCLUSIONS

The RPP is a secondary prevention strategy against CKD which has an effect on the stage progression of CKD and the need for RRT. Early patient detection has a positive effect on the outcomes studied.

Diphlorethohydroxycarmalol Attenuates Methylglyoxal-Induced Oxidative Stress and Advanced Glycation End Product Formation in Human Kidney Cells

Diabetic nephropathy is the leading cause of end-stage renal disease in patients with diabetes mellitus. Oxidative stress has been shown to play an important role in pathogeneses of renal damage in diabetic patients. Here, we investigated the protective effect of diphlorethohydroxycarmalol (DPHC), which is a polyphenol isolated from an edible seaweed, Ishige okamurae, on methylglyoxal-induced oxidative stress in HEK cells, a human embryonic kidney cell line. DPHC treatment inhibited methylglyoxal- (MGO-) induced cytotoxicity and ROS production. DPHC activated the Nrf2 transcription factor and increased the mRNA expression of antioxidant and detoxification enzymes, consequently reducing MGO-induced advanced glycation end product formation. In addition, DPHC increased glyoxalase-1 mRNA expression and attenuated MGO-induced advanced glycation end product formation in HEK cells. These results suggest that DPHC possesses a protective activity against MGO-induced cytotoxicity in human kidney cells by preventing oxidative stress and advanced glycation end product formation. Therefore, it could be used as a potential therapeutic agent for the prevention of diabetic nephropathy.

Angiopoietin-2, Renal Deterioration, Major Adverse Cardiovascular Events and All-Cause Mortality in Patients with Diabetic Nephropathy

BACKGROUND/AIMS

Diabetic nephropathy is the leading cause of end-stage renal disease and accounts for 30∼40% of patients requiring maintenance dialysis, thereby increasing the burden on health insurance programs. Diabetic nephropathy is also the strongest predictor of cardiovascular morbidity and mortality. The aim of this study was to examine whether angiopoietin-2 (Angpt2), a modulator of endothelial function, affects the clinical outcomes of diabetic patients.

METHODS

This study enrolled 236 patients with diabetes mellitus with estimated glomerular filtration rate (eGFR) < 60ml/min/1.73m2 from January 2006 to December 2011, who were followed until June 2017. Clinical outcomes included renal outcomes (commencing dialysis and rapid decline in renal function (eGFR decline > 3 ml/min per 1.73 m2/year)), major adverse cardiovascular events (MACEs), and all-cause mortality.

RESULTS

Over a mean follow-up period of 3.9±2.7 years, 135 (57.2%) patients commenced dialysis, 106 (44.9%) had rapid decline in renal function, and 50 (21.2%) had MACEs or died from all-causes. Log-formed Angpt2 was significantly associated with increased risks of commencing dialysis (HR: 3.91, 95% CI: 1.56-9.76), rapid renal function decline (OR: 6.81, 95% CI: 1.06-43.88), and MACEs or all-cause mortality (HR: 6.34, 95% CI: 1.18-33.97) in the adjusted analysis. Patients in the highest quartile had hazard ratios of 2.90 and 3.11 for commencing dialysis and rapid renal function decline, respectively, compared to those in the lowest quartile after adjustments. Similar significant dose-response results were found in composite outcomes of either MACEs or all-cause mortality.

CONCLUSION

Angpt2 is an independent predictor of adverse clinical outcomes in diabetic patients. Further studies are needed to identify the pathogenic role of Angpt2 in renal deterioration and cardiovascular complications of diabetes mellitus.

Combined effect of body mass index and metabolic status on the risk of prevalent and incident chronic kidney disease: a systematic review and meta-analysis

OBJECTIVE

The risk of chronic kidney disease (CKD) differs in the normal weight, overweight, and obese individuals owing to metabolic abnormality. We aimed to determine the combined effects of body mass index (BMI) and metabolic status on the risk of the prevalence and incidence of CKD.

METHODS

Pubmed, Scopus, Web of science, and abstracts from recently relevant meetings prior to April 2016 were searched to identify eligible studies. Pooled relative risks (RR) and 95% confidence intervals (CI) were calculated using a random effects model.

RESULTS

Eight cross-sectional studies and four longitudinal follow-up studies with a total of 14787 and 166718 participants were separately included in present study. Compared with metabolically healthy normal weight individuals, metabolically healthy obese individuals showed increased risk for CKD, with RR of 1.235 (95%CI: 1.027 to 1.484), while metabolically health overweight individuals still presented in a healthy pattern, RR=1.094(95%CI: 0.774 to 1.547). In addition, metabolically abnormal groups had much higher risk for CKD, with RR of 1.572 (95%CI: 1.373 to 1.801), 1.652(95%CI: 1.139 to 2.397) and 1.898(95%CI: 1.505 to 2.395) across metabolically unhealthy normal weight, overweight and obese individuals respectively.

CONCLUSION

Individuals with abnormal metabolic status are at a significantly elevated risk for CKD, regardless of BMI. For metabolically healthy individuals, CKD risk increases with the growth of BMI, and obese persons eventually have a higher risk.

Chronic kidney disease in Asia: Protocol for a collaborative overview

AIM

The burden of chronic kidney disease (CKD) is growing rapidly around the world. However, there is limited information on the overall regional prevalence of CKD, as well as the prognostic implications and treatment patterns in Asian region. We have established the Asian Renal Collaboration (ARC) with the goal of consolidating region-wide data regarding CKD.

METHODS

This collaborative project will synthesize data and perform meta-analyses of observational studies conducted in Asia. Studies will be identified through a systematic literature search including abstracts, proceedings of meetings, electronic databases such as MEDLINE and EMBASE. Personal enquiry among collaborators and experts in the region will identify additional studies, or other data sources such as registries. Both cross-sectional and longitudinal studies that describe the prevalence of CKD and its complications will be included, as will longitudinal studies that describe important clinical outcomes for people with CKD. Individual participant data will be sought, where possible, from each of the studies included in the collaboration for baseline parameters and subsequent outcomes, in order to maximize flexibility and consistency of data analyses.

CONCLUSIONS

This study is an initiative offering a unique opportunity to obtain information about the prevalence and manifestations of CKD in Asia, as well as its risk factors. The ARC will also provide insights into important outcomes including progression of CKD, CKD complications, cardiovascular disease and death. These findings will improve our understanding of kidney disease in Asia, and thus help inform service provision, preventive care and further research across the region.

Mitochondrial dysfunction in diabetic kidney disease

Globally, diabetes is the leading cause of chronic kidney disease and end-stage renal disease, which are major risk factors for cardiovascular disease and death. Despite this burden, the factors that precipitate the development and progression of diabetic kidney disease (DKD) remain to be fully elucidated. Mitochondrial dysfunction is associated with kidney disease in nondiabetic contexts, and increasing evidence suggests that dysfunctional renal mitochondria are pathological mediators of DKD. These complex organelles have a broad range of functions, including the generation of ATP. The kidneys are mitochondrially rich, highly metabolic organs that require vast amounts of ATP for their normal function. The delivery of metabolic substrates for ATP production, such as fatty acids and oxygen, is altered by diabetes. Changes in metabolic fuel sources in diabetes to meet ATP demands result in increased oxygen consumption, which contributes to renal hypoxia. Inherited factors including mutations in genes that impact mitochondrial function and/or substrate delivery may also be important risk factors for DKD. Hence, we postulate that the diabetic milieu and inherited factors that underlie abnormalities in mitochondrial function synergistically drive the development and progression of DKD.

SOCS2 overexpression alleviates diabetic nephropathy in rats by inhibiting the TLR4/NF-κB pathway

Suppressor of cytokine signaling 2 (SOCS2) was reported to be involved in the development of Diabetic Nephropathy (DN). However, its underlying mechanism remains undefined. Western blot was carried out to determine the expressions of SOCS2, Toll-like receptors 4 (TLR4) and nuclear factor kappa B (NF-κB) pathway-related proteins in DN patients, streptozotocin (STZ)-induced DN rats and high glucose (HG)-stimulated podocytes. The effects of SOCS2 overexpression on renal injury, the inflammatory cytokines production, renal pathological changes, apoptosis and the TLR4/NF-κB pathway in DN rats or HG-stimulated podocytes were investigated. TLR4 antagonist TAK-242 and NF-κB inhibitor PDTC were used to confirm the functional mechanism of SOCS2 overexpression in HG-stimulated podocytes. SOCS2 was down-regulated, while TLR4 and NF-κB were up-regulated in renal tissues of DN patients and DN rats. Ad-SOCS2 infection alleviated STZ-induced renal injury and pathological changes and inhibited STZ-induced IL-6, IL-1β and MCP-1 generation and activation of the TLR4/NF-κB pathway in DN rats. SOCS2 overexpression attenuated apoptosis, suppressed the inflammatory cytokines expression, and inactivated the TLR4/NF-κB pathway in HG-stimulated podocytes. Suppression of the TLR4/NF-κB pathway enhanced the inhibitory effect of SOCS2 overexpression on apoptosis and inflammatory cytokines expressions in HG-stimulated podocytes. SOCS2 overexpression alleviated the development of DN by inhibiting the TLR4/NF-κB pathway, contributing to developing new therapeutic strategies against DN.

Angiotensin II induces kidney inflammatory injury and fibrosis through binding to myeloid differentiation protein-2 (MD2)

Growing evidence indicates that angiotensin II (Ang II), a potent biologically active product of RAS, is a key regulator of renal inflammation and fibrosis. In this study, we tested the hypothesis that Ang II induces renal inflammatory injury and fibrosis through interaction with myeloid differentiation protein-2 (MD2), the accessory protein of toll-like receptor 4 (TLR4) of the immune system. Results indicated that in MD2^−/− mice, the Ang II-induced renal fibrosis, inflammation and kidney dysfunction were significantly reduced compared to control Ang II-infused wild-type mice. Similarly, in the presence of small molecule MD2 specific inhibitor L6H21 or siRNA-MD2, the Ang II-induced increases of pro-fibrotic and pro-inflammatory molecules were prevented in tubular NRK-52E cells. MD2 blockade also inhibited activation of NF-κB and ERK. Moreover, MD2 blockade prevented the Ang II-stimulated formation of the MD2/TLR4/MyD88 signaling complex, as well as the increased surface binding of Ang II in NRK-52E cells. In addition, Ang II directly bound recombinant MD2 protein, rather than TLR4 protein. We conclude that MD2 is a significant contributor in the Ang II-induced kidney inflammatory injury in chronic renal diseases. Furthermore, MD2 inhibition could be a new and important therapeutic strategy for preventing progression of chronic renal diseases.

Preliminary Results of a Newly Established Organ Transplantation Program in a Teaching Hospital

OBJECTIVES

End-stage renal disease is the complete failure of kidney function; kidney transplant offers the best survival advantage. We analyzed data from Al-Basheer Hospital's newly established transplant program and present our kidney transplant results from the first year of operation.

MATERIALS AND METHODS

Between April 2015 and June 2016, 20 kidney transplants were performed (19 living-related donors and 1 deceased donor). We assessed the demographic data, surgical techniques employed, complications, immunosuppressive drugs used, and graft and patient survival rates. The mean recipient age was 32.8 years. There were 10 male and 10 female patients. Two patients underwent preemptive transplant, and 18 were on hemodialysis. Preparation of the donor and recipient employed an established transplant protocol. Induction immunosuppression therapy was used in 13.65% of patients. The left kidney was used from all living donors, and the right kidney was harvested from the deceased donor. The total ischemia time in the living-donor grafts ranged from 30 to 53 minutes; in the deceased donor, the ischemia time was 90 minutes. Intraoperative Doppler ultrasonography was used in most cases.

RESULTS

There was no donor mortality, and no significant donor complications occurred, either intraoperatively or postoperatively. There was no recipient mortality, but there were complications in 6 patients. Intraoperative complications were reported in 2 patients: 1 with renal artery thrombosis and the other with external iliac artery dissection. Postoperative complications were reported in 4 patients: slow graft function in 1 patient with thrombotic thrombocytopenic purpura, 1 patient with acute cellular rejection treated with intravenous immunoglobulin, 1 patient with cytomegalovirus gastroenteritis, and 1 patient treated for varicella pneumonitis. The follow-up ranged from 1 week to 13 months.

CONCLUSIONS

The first-year outcomes for our newly established transplant program at Al-Basheer Hospital are comparable to those of well-established programs.

Toll-like receptor 2 agonist exacerbates renal injury in diabetic mice

Inflammation is implicated in the pathogenesis of diabetic nephropathy (DN). Toll-like receptor 2 (TLR2) is a ligand-activated membrane-bound receptor, which induces an inflammatory response, thus serving a crucial role in the pathogenesis of DN. The present study aimed to determine whether a TLR2 agonist, Pam₃CysSK_4, modulates the development of DN. A mouse model of DN was induced using streptozotocin (STZ) and, following the confirmation of hyperglycemia, mice were treated with or without Pam₃CysSK₄. Pathological and functional markers, including the activation of nuclear factor (NF)-κB, expression of TLR2, inflammatory infiltration, myeloid differentiation primary response gene 88 and monocyte chemoattractant protein-1 were assessed. STZ-treated mice exhibited elevated blood glucose levels and increased serum creatinine levels, which increased further following Pam₃CysSK₄ treatment. In addition, Pam₃CysSK₄ treatment was observed to increase podocyte foot process formation. Furthermore, STZ-induced renal glomerular sclerosis was significantly exacerbated in Pam₃CysSK₄-treated mice. Pam₃CysSK₄-treated mice also exhibited increased levels of collagen IV following renal immunostaining, associated with increased macrophage infiltration. Renal expression of TLR2 was markedly elevated in STZ-induced mice; this was further increased in Pam₃CysSK₄-treated mice, accompanied by upregulation of proinflammatory genes and activation of NF-κB. This indicates that enhanced renal expression of TLR2 is associated with inflammatory infiltration in DN and demonstrates that renal injury was exacerbated by the TLR2 agonist in diabetic mice.

Health economic evaluation of paricalcitol(®) versus cinacalcet + calcitriol (oral) in Italy. [corrected]

BACKGROUND AND OBJECTIVE

Chronic kidney disease (CKD) is a highly morbid disorder. The most severe form of CKD is end-stage renal disease (ESRD), in which the patient requires some form of renal replacement therapy to survive. The increasing incidence, prevalence, and costs of ESRD are major national healthcare concerns. The objective of this study was to determine the cost effectiveness of two innovative therapies, paricalcitol versus cinacalcet + calcitriol (oral) in patients with CKD stage 5 (CKD 5) in the healthcare setting in Italy in 2013.

METHODS

A Markov process model was developed employing data sources from the published literature, paricalcitol clinical trials, official Italian price/tariff lists, and national population statistics. The analysis is based on a comparison of treatment with paricalcitol versus cinacalcet + calcitriol (oral) in CKD 5. The perspective of the study was that of the payer [Italian National Health Service (INHS)]. The primary efficacy outcomes in the paricalcitol and cinacalcet + calcitriol (oral) clinical trials (reduction of secondary hyperparathyroidism, complications, and mortality) were extrapolated to effectiveness outcomes: number of life-years gained (LYG) and number of quality-adjusted life-years (QALYs). Clinical and economic outcomes were discounted at 3 %.

RESULTS

The base-case analysis is based on a 5-year time horizon. From the INHS perspective, the use of paricalcitol leads to a cost saving of €1,853 and an increase in LYG (0.136) and a gain in QALYs (0.089). Consequently, the use of paricalcitol is dominant over the use of combination cinacalcet + calcitriol (oral paricalcitol leads to cost savings and a higher effectiveness). Sensitivity analyses confirmed the robustness of the model.

CONCLUSION

The results showed that the favorable clinical benefit of paricalcitol results in positive health economic benefits. This study suggests that the use of paricalcitol in patients with ESRD may be cost effective from the perspective of the INHS.

Effects of p53 on aldosterone-induced mesangial cell apoptosis in vivo and in vitro

Aldosterone (ALD) is a well‑known hormone, which may initiate renal injury by inducing mesangial cell (MC) injury in chronic kidney disease (CKD); however, the molecular mechanism remains unknown. The aim of the present study was to investigate the effects of p53 on ALD‑induced MC apoptosis and elucidate the underlying molecular mechanism. For the in vivo studies, rats were randomly assigned to receive normal saline or ALD for 4 weeks. The ratio of MC apoptosis was analysed by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay. In addition, the expression level and localisation of p53, a well-known cell apoptosis-associated key protein, were detected by immunofluorescence. For the in vitro studies, rat MCs were incubated in medium containing either buffer (control) or ALD (10‑6 M) for 24 h. The cell apoptosis ratio was assessed by flow cytometry, and the expression level of p53 was assessed by reverse transcription quantitative polymerase chain reaction and western blotting. In order to confirm the role of p53 in ALD‑regulated cell apoptosis, a rescue experiment was performed using targeted small interfering (si)RNA to downregulate the expression of p53. The ALD‑treated rats exhibited greater numbers of TUNEL‑positive MCs and higher expression levels of p53 when compared with the control group. Furthermore, the ratio of MC apoptosis and the p53 expression level were significantly increased following ALD exposure, compared with the control group. Additionally, in the rescue experiment, the effects of ALD on MC were blocked by downregulating the expression level of p53 in MCs. The present study hypothesized that ALD may directly contribute to the occurrence of MC apoptosis via p53, which may participate in ALD-induced renal injury.

Psychometric Evaluation of the Vietnamese Hemodialysis Stressor Scale

The lack of a suitable assessment tool may limit optimal stress management and impair the health-related quality of life of patients undergoing hemodialysis. The purpose of the study was to examine latent constructs and psychometric properties of the Vietnamese Hemodialysis Stressor Scale (HSS-V). In total, 180 patients receiving hemodialysis were recruited. Psychometric properties of the HSS-V, including the construct validity, internal consistency, and test-retest reliability, were tested after the instrument translation. The exploratory factor analysis resulted in a 24-item HSS-V with four extracted factors, which explained 58.32% of the total variance. The construct validity was confirmed by significant negative correlations between scores on the HSS-V and Vietnamese-version Short Form-36. The internal consistency (Cronbach's α = .82-.91) and test-retest reliability (intra-class correlations coefficient = .91-.94) of the 24-item HSS-V were satisfactory. A simple structure and preliminary acceptable psychometric properties of the HSS-V were established and can serve as a basis for further studies.

Inflammation

Inflammation was described as early as 3000 BC in an Egyptian papyrus [1] and is still a common problem despite continuous advancements in prevention and treatment methods. The delineation of the site and extent of inflammation are crucial to the clinical management of infection and for monitoring the response to therapy [2].

Metabolic abnormalities, but not obesity, contribute to the mildly reduced eGFR in middle-aged and elderly Chinese

BACKGROUND

The role of obesity as a determinant of kidney dysfunction has not reached an agreement and the underlying reason may be due to the heterogeneity of obese phenotypes. The aim of the study was to explore the associations of different obese phenotypes with the change of estimated glomerular filtration rate (eGFR) and the roles of obesity and metabolic abnormalities in this association.

METHODS

eGFR was calculated in 8,586 participants (≥ 40 years old). eGFR 60-90 mL/min/1.73 m(2) was defined as the mildly reduced eGFR. Multiple logistic regression analysis was used to determine odds ratios (ORs) for mildly reduced eGFR in the metabolically healthy obese (MHO), metabolically abnormal non-obese (MANO) and metabolically abnormal obese (MAO) groups, using the metabolically healthy non-obese (MHNO) subjects as the reference group. Meanwhile, the associations of body mass index (BMI), waist circumference (WC) and metabolic abnormalities (including hypertension, hyperglycemia and dyslipidemia) with the risk of mildly reduced eGFR were also investigated.

RESULTS

The proportion of MHNO, MHO, MANO and MAO subjects was 8.3, 17.1, 10.1 and 64.5 %, respectively. Increased ORs were observed in MANO (OR 1.51, P = 0.014) and MAO (OR 1.47, P = 0.015) groups, after adjusting for age, gender, smoking, drinking, BMI and WC. When further adjusting for metabolic abnormalities, MANO (OR 1.24, P = 0.247) and MAO (OR 1.17, P = 0.366) subjects would not present increased risk of mildly reduced eGFR any more. Oppositely, fasting insulin (OR 1.03, P < 0.001), hyperglycemia (OR 1.25, P = 0.002) and dyslipidemia (OR 1.25, P = 0.002), but not hypertension, BMI and WC, significantly increased the risk of mildly reduced eGFR.

CONCLUSIONS

Metabolic abnormalities, but not simple obesity, may contribute to the mildly reduced eGFR in middle-aged and elderly Chinese.

TLR4 activation promotes podocyte injury and interstitial fibrosis in diabetic nephropathy

Toll like receptor (TLR) 4 has been reported to promote inflammation in diabetic nephropathy. However the role of TLR4 in the complicated pathophysiology of diabetic nephropathy is not understood. In this study, we report elevated expression of TLR4, its endogenous ligands and downstream cytokines, chemokines and fibrogenic genes in diabetic nephropathy in WT mice with streptozotocin (STZ) diabetes. Subsequently, we demonstrated that TLR4^−/− mice were protected against the development of diabetic nephropathy, exhibiting less albuminuria, inflammation, glomerular hypertrophy and hypercellularity, podocyte and tubular injury as compared to diabetic wild-type controls. Marked reductions in interstitial collagen deposition, myofibroblast activation (α-SMA) and expression of fibrogenic genes (TGF-β and fibronectin) were also evident in TLR4 deficient mice. Consistent with our in vivo results, high glucose directly promoted TLR4 activation in podocytes and tubular epithelial cells in vitro, resulting in NF-κB activation and consequent inflammatory and fibrogenic responses. Our data indicate that TLR4 activation may promote inflammation, podocyte and tubular epithelial cell injury and interstitial fibrosis, suggesting TLR4 is a potential therapeutic target for diabetic nephropathy.

Role of Toll-like receptors in diabetic nephropathy

Diabetic nephropathy is the leading cause of kidney failure and its increasing prevalence and incidence has imposed global socio-economic stress on healthcare systems worldwide. Although historically considered a metabolic disorder, recent studies have established that inflammatory responses are central to the pathogenesis of diabetic nephropathy. TLRs (Toll-like receptors) are a family of pattern recognition receptors responsible for the initiation of inflammatory and immune responses. The regulation of TLR2 and TLR4 have been implicated in the pathogenesis of various kidney diseases, and emerging evidence shows their involvement in the perpetuation of inflammation in the diabetic kidney. The present review focuses on the relative contributions of TLR2 and TLR4 in recognizing endogenous ligands relevant to diabetic nephropathy and their subsequent activation of NF-κB (nuclear factor κB), which results in the synthesis and secretion of pro-inflammatory cytokines and chemokines. Moreover, we discuss the pro-inflammatory signalling pathways of TLR2 and TLR4, in which their interruption or blockade may prove to be important therapeutic targets, potentially translated into clinical treatments for diabetic nephropathy. Currently, inhibitors to TLR2 and TLR4 are undergoing clinical trials in various inflammatory models of disease, but none in patients with diabetic nephropathy. Given the existing literature, there is a fundamental necessity to undertake trials in patients with diabetic nephropathy with a focus on renal end points.

Renal diseases in haemophilic patients: pathogenesis and clinical management

Haemophilia A and B are genetic X-linked bleeding disorders, caused by mutations in genes encoding factors VIII and IX, respectively. Clinical manifestations of haemophilia are spontaneous haemorrhage or acute bleeding caused by minor trauma, resulting in severe functional consequences that can culminate in a debilitating arthropathy. Life expectancy and quality of life of patients with haemophilia have dramatically improved over the last years, mainly for new therapeutic options and the awareness to the risk of HCV and HIV infections. Different clinical problems arise from this important change in history of patients with haemophilia. In particular, ageing-related diseases, such as diabetes, hypertension and cancer, and chronic viral infections are emerging as new challenges in this patient population. Among the different types of chronic illnesses, renal diseases are of special interest as they involve some difficult management issues. In fact, decisions regarding adequate preventive strategies and viral infection treatment, the choice of the dialytic modality, placement of vascular access and prescription of dialytic treatments are particularly complicated, because only few data are available. In this review, we discuss the pathogenesis of renal damage in patients with haemophilia, especially in those with blood-transmitted viral infections, and the major issues about the management of renal diseases, including problems related to dialytic treatment and kidney transplantation, providing practical algorithms to guide the clinical decision-making process.

Health-related quality of life in hemodialysis patients: an Iranian multi-center study

Background

The effectiveness of health care and health policy developments are often determined by health-related quality of life (HRQOL) assessment.

Objectives

The objective of this study was to explore the potential corresponding factors and traditional biomarkers of HRQOL in a large number of Iranian hemodialysis patients.

Patients and Methods

A total of 6,930 chronic hemodialysis (HD) patients enrolled. KDCS-SF version 1.3 questionnaire was used to assess the health related quality of life (HRQOL). We pooled PCS, MCS and KDCS scores with random effect model from 19 similar studies performed between 1996 and 2010

Results

The mean age was 54.4 ± 17.1 years. Mean PCS, MCS and KDCS scores obtained for the study cohort were 40.79 ± 20.10, 47.79 ± 18.31 and 57.97 ± 11.70, respectively; the total score of SF-36 plus KDCS was 51.12 ± 13.41 as well. The most common primary known disease was hypertension (31.9%) and the second etiology was diabetes (25.5%). In multilevel logistic regression, Kt/V between 1 and 1.2 and PCS, KDCS more than 50 were considered as a significant reduction in the risk of hospitalization.

Conclusions

This study showed that PCS and MCS score were slightly more than overall results while KDCS was slightly less than overall results. In addition, dialysis adequacy with Kt/V between 1 and 1.2 is associated with lower rate of hospitalization.

The prevalence of chronic kidney disease in a primary care setting: a Swiss cross-sectional study

Chronic kidney disease (CKD) often remains clinically silent and therefore undiagnosed until a progressed stage is reached. Our aim was to estimate the prevalence of CKD in a primary care setting in Switzerland. A multicenter, cross-sectional study with randomly selected general practitioners was performed. Adults visiting their general physician’s cabinet during defined periods were asked to participate. Baseline information was reported on a questionnaire, urine and blood samples were analyzed in a central laboratory. Renal status was assessed using the Kidney Disease: Improving Global Outcomes (KDIGO) classification. Extrapolation of results to national level was adjusted for age and gender. One thousand individuals (57% females) with a mean age of 57±17 years were included. Overall, 41% of the patients had normal estimated glomerular filtration rate (eGFR) and albumin creatinine ratio (ACR), whereas 36% of the subjects had slightly reduced excretory renal function with physiological albuminuria based on normal ACR. Almost one fourth of the subjects (23%) had either a substantially reduced eGFR or high levels of ACR. About 10% of the patients had a substantially reduced eGFR of <60 ml/min/1.73 m², and 17% showed relevant proteinuria (ACR >30 mg/g creatinine). Extrapolation to national level suggests that about 18% of primary care patients may suffer from CKD. CKD prevalence in a primary care population is therefore high, and preventive interventions may be advisable, in particular as CKD prevalence is likely to rise over the next decades.

The role of Toll-like receptor proteins (TLR) 2 and 4 in mediating inflammation in proximal tubules

Inflammatory responses are central to the pathogenesis of diabetic nephropathy. Toll-like receptors (TLRs) are ligand-activated membrane-bound receptors which induce inflammatory responses predominantly through the activation of NF-κB. TLR2 and 4 are present in proximal tubular cells and are activated by endogenous ligands upregulated in diabetic nephropathy, including high-mobility group box-1 (HMGB1) and fibronectin. Human proximal tubules were exposed to 5 mM (control), 11.2 mM (approximating the clinical diagnostic threshold for diabetes mellitus), and 30 mM (high) glucose for 72 h or 7 days. Cells were harvested for protein, mRNA, and nuclear extract to assess for TLR2, 4, and inflammatory markers. Glucose (11.2 mM) maximally increased TLR2 and 4 expression, HMGB1 release, and NF-κB activation with increased expression of cytokines. However, only TLR2 expression and subsequent NF-κB binding were sustained at 7 days. Recombinant HMGB1 induced NF-κB activation, which was prevented by both TLR2 silencing [small interfering (si)RNA] and TLR4 inhibition. Peroxisome proliferator-activated receptor-γ (PPAR-γ) transcription was reduced by exposure to 11.2 mM glucose with an increase observed at 30 mM glucose at 24 h. This may reflect a compensatory increase in PPAR-γ induced by exposure to 30 mM glucose, limiting the inflammatory response. Therefore, short-term moderate increases in glucose in vitro increase HMGB1, which mediates NF-κB activation through both TLR2 and 4. Furthermore, in vivo, streptozotocin-induced diabetic mice exhibited an increase in tubular TLR2 and HMGB1 expression. These results collectively suggest that TLR2 is likely to be the predominant long-term mediator of NF-κB activation in transducing inflammation in diabetic nephropathy.

Population screening for chronic kidney disease: a survey involving 38,721 Brazilians

BACKGROUND

It is known that chronic kidney disease (CKD) is continuously increasing all over the world, but the available numbers of affected subjects are mostly collected from renal replacement therapy services and they correspond to individuals with end-stage renal disease. The aim of the present study was to diagnose CKD in its earliest stages in the general population based on detection of proteinuria.

METHODS

In public prevention campaigns, from 2005 to 2010, 38 721 inhabitants were evaluated in the state of Sao Paulo (Brazil). Screening procedures included a dipstick test, blood pressure measurement and application of a medical questionnaire.

RESULTS

In the whole population, urine samples of 37 771 individuals (mean age: 44.59 + 21.70, 55.74% females) were evaluated, 7.3% presented proteinuria (1+ or more) in the screening test and 85.5% of them had no previous knowledge of this urinary abnormality. Those individuals were referred for further clinical evaluation in order to confirm the detected alterations. Considering being diabetic and/or hypertensive as important risk factors for CKD, it was observed that they corresponded to 9.7 and 28.4% of the population screened for proteinuria, respectively. Newly detected cases of possible CKD, diabetes and hypertension corresponded to 6.2, 0.3 and 6.5%, respectively.

CONCLUSIONS

This initiative provided information on proteinuria and possible cases of CKD based on a large sampling of the Brazilian population. Proteinuria was detected in 7.3% of these individuals, and such prevalence is similar to that previously described in developed countries.

Psychiatric disorders in patients with end-stage renal disease

Psychiatric disorders in patients with end-stage renal disease are associated with poor prognosis and quality of life. The goal of this study is to investigate the association between psychiatric disorders and renal disease in patients undergoing dialysis treatment, compared with other chronic diseases, appreciating the demographic status of these patients. Sixty-nine patients participated in a diagnostic interview and gave socio-demographic data. The population was composed of 55% men aged 19-77 years with an average age of 50 years (95% CI = 47-54 years). The prevalence of psychiatric disorders found in this study (46.6%) was compared with that found in patients with asthma, polycystic ovary syndrome and HIV-positive. Moreover, the prevalence of the four most common psychiatric disorders which were identified among patients on dialysis were also the subject of comparison between them and others. These results demonstrate the relationship between the various psychiatric disorders and are compatible with other research studies.

Ubiquinone (coenzyme Q10) prevents renal mitochondrial dysfunction in an experimental model of type 2 diabetes

Cardiovascular benefits of ubiquinone have been previously demonstrated, and we administered it as a novel therapy in an experimental model of type 2 diabetic nephropathy. db/db and dbH mice were followed for 10 weeks, after randomization to receive either vehicle or ubiquinone (CoQ10; 10mg/kg/day) orally. db/db mice had elevated urinary albumin excretion rates and albumin:creatinine ratio, not seen in db/db CoQ10-treated mice. Renal cortices from db/db mice had lower total and oxidized CoQ10 content, compared with dbH mice. Mitochondria from db/db mice also contained less oxidized CoQ10(ubiquinone) compared with dbH mice. Diabetes-induced increases in total renal collagen but not glomerulosclerosis were significantly decreased with CoQ10 therapy. Mitochondrial superoxide and ATP production via complex II in the renal cortex were increased in db/db mice, with ATP normalized by CoQ10. However, excess renal mitochondrial hydrogen peroxide production and increased mitochondrial membrane potential seen in db/db mice were attenuated with CoQ10. Renal superoxide dismutase activity was also lower in db/db mice compared with dbH mice. Our results suggest that a deficiency in mitochondrial oxidized CoQ10 (ubiquinone) may be a likely precipitating factor for diabetic nephropathy. Therefore CoQ10 supplementation may be renoprotective in type 2 diabetes, via preservation of mitochondrial function.

Prevalence of chronic kidney disease in Thai adults: a national health survey

Background

The prevalence of patients with end stage renal disease (ESRD) who need dialysis and/or transplantation has more than doubled in Thailand during the past two decades. It has been suggested that therapeutic strategies to reduce the risk of ESRD and other complications in CKD are now available, thus the early recognition and the institution of proven therapeutic strategies are important and beneficial. We, therefore, aimed to determine the prevalence of CKD in Thai adults from the National Health Examination Survey of 2004.

Methods

Data from a nationally representative sample of 3,117 individuals aged 15 years and older was collected using questionnaires, physical examination and blood samples. Serum creatinine was measured by Jaffé method. GFR was estimated using the Chinese modified Modification of Diet in Renal Disease Study equation. Chronic kidney Disease (CKD) stages were classified based on Kidney Disease Outcome Quality Initiative (K/DOQI).

Results

The prevalence of CKD in Thai adults weighted to the 2004 Thai population by stage was 8.1% for stage 3, 0.2% and 0.15% for stage 4 and 5 respectively. Compared to non-CKD, individuals with CKD were older, had a higher level of cholesterol, and higher blood pressure. Those with cardiovascular risk factors were more likely to have CKD (stage 3-5) than those without, including hypertension (OR 1.6, 95%CI 1.1, 3.4), diabetes (OR 1.87, 95%CI 1.0, 3.4). CKD was more common in northeast (OR 2.1, 95%CI 1.3, 3.3) compared to central region. Urinalysis was not performed, therefore, we could not have data on CKD stage 1 and 2. We have no specific GFR formula for Thai population.

Conclusion

The identification of CKD patients should be evaluated and monitored for appropriate intervention for progression to kidney disease from this screening.

An update on renal replacement therapy in Europe: ERA-EDTA Registry data from 1997 to 2006

BACKGROUND

Recent studies have indicated a stabilization in the incidence rates of renal replacement therapy (RRT) for end-stage renal disease (ESRD) in a number of European countries. The aim of this study was to provide an update on the incidence, prevalence and outcomes of RRT in Europe over the past decade.

METHODS

Nineteen European national or regional renal registries with registry data from 1997 to 2006 participated in the study. Incidence and prevalence trends were analysed with Poisson and Joinpoint regression. Cox regression methods were used to examine patient survival.

RESULTS

The total adjusted incidence rate of RRT for ESRD increased from 109.9 per million population (pmp) in 1997 to 119.7 pmp in 2000, i.e. an average annual percentage change (AAPC) of 2.9% (95% CI 2.1-3.8%). Thereafter, the incidence increased at a much lower rate to 125.4 pmp in 2006 [AAPC 0.6% (95% CI 0.3-0.8%)]. This change in the trend of the incidence of RRT was largely due to a stabilization in the incidence rates of RRT for females aged 65-74 years, males aged 75-84 years and patients receiving RRT for ESRD due to hypertension/renal vascular disease. The overall adjusted prevalence in Europe continued to increase linearly at 2.7% per year. Between the periods 1997-2001 and 2002-2006, the risk of death decreased for all treatment modalities, with the most substantial improvement in patients starting peritoneal dialysis [19% (95% CI 15-22%)] and in patients receiving a kidney transplant [17% (95% CI 11-23%)].

CONCLUSION

This European study shows that the annual rise of the overall incidence rate of RRT for ESRD has diminished and that in several age groups the incidence rates have now stabilized. The survival of dialysis patients and kidney transplant recipients has continued to improve.

Combination therapy with paricalcitol and trandolapril reduces renal fibrosis in obstructive nephropathy

Growing evidence suggests that active vitamin D slows the progression of chronic kidney diseases. Here we compared the individual renal protective efficacy of paricalcitol and trandolapril (an angiotensin-converting enzyme inhibitor) in obstructive nephropathy, and examined any potential additive effects of their combination on attenuating renal fibrosis and inflammation. Mice underwent unilateral ureteral obstruction and were treated individually with paricalcitol or trandolapril or their combination. Compared to vehicle-treated controls, monotherapy with paricalcitol or trandolapril inhibited the expression and accumulation of fibronectin and type I and type III collagen, suppressed alpha-smooth muscle actin, vimentin, and Snail1 expression, and reduced total collagen content in the obstructed kidney. Combination therapy led to a more profound inhibition of all parameters. Monotherapy also suppressed renal RANTES (regulated on activation, normal T cell expressed and secreted) and tumor necrosis factor (TNF)-alpha expression and inhibited renal infiltration of T cells and macrophages, whereas the combination had additive effects. Renin expression was induced in the fibrotic kidney and was augmented by trandolapril. Paricalcitol blocked renin induction in the absence or presence of trandolapril. Our study indicates that paricalcitol has renal protective effects, comparable to that of trandolapril, in reducing interstitial fibrosis and inflammation. Combination therapy had additive efficacy in retarding renal scar formation during obstructive nephropathy.

Blood pressure is a major risk factor for renal death: an analysis of 560 352 participants from the Asia-Pacific region

Chronic kidney disease is a major worldwide public health problem that causes substantial morbidity and mortality. Studies from the Asia-Pacific region have reported some of the highest chronic kidney disease prevalence rates in the world, but access to dialysis is limited in many countries, making it imperative to identify high-risk individuals. We performed a participant-level data overview of prospective studies conducted in the Asia-Pacific region to quantify the magnitude and direction of the associations between putative risk factors and renal death. Age- and sex-adjusted Cox proportional hazards models were applied to pooled data from 35 studies to calculate hazard ratios (95% CIs) for renal death associated with a standardized change in risk factors. Among 560 352 participants followed for a median of 6.8 years, a total of 420 renal deaths were observed. Continuous and positive associations among systolic blood pressure, diastolic blood pressure, fasting blood glucose, and total cholesterol levels with renal death were observed, as well as a continuous but inverse association with high-density lipoprotein cholesterol. Systolic blood pressure was the strongest risk factor for renal death with each SD increase in systolic blood pressure (19 mm Hg) associated with >80% higher risk (hazard ratio: 1.84; 95% CI: 1.60 to 2.12). Neither cigarette smoking nor excess weight was related to the risk of renal death (P>0.10). The results were similar for cohorts in Asia and Australia. These results suggest that primary prevention strategies for renal disease should focus on individuals with elevated blood pressure, diabetes mellitus, and dyslipidemia.

Chronic kidney disease Markov model comparing paricalcitol to calcitriol for secondary hyperparathyroidism: a US perspective

OBJECTIVE

The objective of this study was to determine the cost effectiveness of paricalcitol versus calcitriol for the treatment of secondary hyperparathyroidism in patients with chronic kidney disease in the United States setting.

METHODS

A Markov process model was developed employing data sources from the published literature, paricalcitol clinical trials and observational studies, official US price/tariff lists and national population statistics. The comparator was calcitriol, a non-selective vitamin D receptor activator (VDRA) medication. The primary perspective of the study was that of the third-party payer in the US. The efficacy outcomes (reduction in secondary hyperparathyroidism (SHPT), reduction in proteinuria, complications and mortality) were extrapolated to: number of life-years gained (LYG) and number of quality-adjusted life-years (QALYs). Clinical and economic outcomes were discounted at 3.5%.

RESULTS

The reference case analysis was a 10-year time horizon based on a comparison of paricalcitol with calcitriol, which is started in chronic kidney disease (CKD) stage 3 and continued in CKD stage 4 and CKD stage 5. The use of paricalcitol leads to a cost saving of US$1941. The inclusion of indirect costs leads to a cost saving of US$2528. The use of paricalcitol leads to an increase in life-years gained (0.47 years) and a gain in QALYs (0.43). The use of paricalcitol results in a dominant outcome from the perspective of the third-party payer, as well as from the societal perspective. One-way sensitivity analyses and probabilistic sensitivity analyses confirmed the robustness of the model.

CONCLUSION

This model showed that the favorable clinical benefit of paricalcitol results in positive short and long-term health economic benefits. This study suggests that the use of paricalcitol in patients with early chronic kidney disease may be cost-effective from the third-party payer perspective in the US versus calcitriol. Additional comparative studies are necessary to validate these results.