DNA methylation (DNAm) clocks are important biomarkers of cellular aging and are associated with a variety of age-related chronic diseases and all-cause mortality. Examining the relationship between education and lifestyle risk factors for age-related diseases and multiple DNAm clocks can increase the understanding of how risk factors contribute to aging at the cellular level. This study explored the association between education or lifestyle risk factors for age-related diseases and the acceleration of four DNAm clocks, including intrinsic (IEAA) and extrinsic epigenetic age acceleration (EEAA), PhenoAge acceleration (PhenoAA), and GrimAge acceleration (GrimAA) in the African American participants of the Genetic Epidemiology Network of Arteriopathy. We performed both cross-sectional and longitudinal analyses. In cross-sectional analyses, gender, education, BMI, smoking, and alcohol consumption were all independently associated with GrimAA, whereas only some of them were associated with other clocks. The effect of smoking and education on GrimAA varied by gender. Longitudinal analyses suggest that age and BMI continued to increase GrimAA, and that age and current smoking continued to increase PhenoAA after controlling DNAm clocks at baseline. In conclusion, education and common lifestyle risk factors were associated with multiple DNAm clocks. However, the association with each risk factor varied by clock, which suggests that different clocks may capture adverse effects from different environmental stimuli.

Education and Lifestyle Factors Are Associated with DNA Methylation Clocks in Older African Americans.

Early detection of drug-induced kidney injury is vital in drug development. Generally accepted biomarkers such as creatinine and blood urea nitrogen (BUN) lack sensitivity and early injury responses are missed. Many new biomarkers to detect nephrotoxicity for pre-clinical utilization have been described and their use is adopted in regulatory guidelines. However, guidance on appropriate biomarkers for clinical trials is minimal. We provide an overview of potentially useful kidney biomarkers that can be used in clinical trials. This includes guidance to select biomarkers suitable to capture specific characteristics of the (expected) kidney injury. We conclude that measurement of urinary kidney injury marker-1 (KIM-1) serves many purposes and is often an appropriate choice. Cystatin C captures effects on glomerular filtration rate (GFR), but this marker should preferably be combined with more specific markers to localize the origin of the observed effect. Untoward effects on tubules can be captured relatively well with several markers. Direct detection of glomerular injury is currently impossible since specific biomarkers are lacking. Indirect assessment of toxic effects on glomeruli is possible by using carefully selected panels of other injury markers. We conclude that it is possible to obtain appropriate information on nephrotoxicity in clinical drug development by using carefully selected panels of injury markers and suggest that identification and validation of specific glomerular biomarkers could be of great value.

https://bpspubs.onlinelibrary.wiley.com/doi/pdf/10.1111/bcp.12282

Urinary kidney biomarkers for early detection of nephrotoxicity in clinical drug development.

Renal involvement in hepatitis B occurs in various spectrums and its knowledge is important for clinicians in management of patients. The renal diseases most commonly associated with hepatitis B virus (HBV) infection include membranous nephropathy, membranoproliferative glomerulonephritis and Polyarteritis nodosa. The widespread use of hepatitis B vaccination has decreased the incidence of HBV-related renal diseases. The incidence of HBV infection in dialysis patients has significantly decreased over the past few decades because of screening of blood products for hepatitis B surface antigen (HBsAg) and hepatitis B core antibody, implementation of infection control measures and hepatitis B vaccination. The definition of acute kidney injury has been recently modified in cirrhotic population, helping in prognosis and prediction of mortality. The most common etiologies of acute kidney injury in this cirrhotic population, which account for 80% to 90% of all cases, include volume depletion, acute tubular necrosis and hepatorenal syndrome. Treatment with oral nucleoside/tide analogues (NA) brought a new paradigm in the management of HBsAg positive glomerulonephritis, kidney transplant recipients and dialysis patients, resulting in effective viral suppression, reduced hepatic complications and improved patient survival, without compromising renal allograft outcome. NAs are cleared by the kidneys and therefore their dosage has to be adjusted in all patients with impaired renal function. This article reviews the recent knowledge of the pathogenesis and treatment of HBV-related glomerulonephritis and discusses the management of hepatitis B in patients on dialysis, kidney transplant recipients and cirrhotics, which is continuously evolving.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/liv.13498

Spectrum of Hepatitis B and Renal Involvement

Cadmium and mercury are among the most toxic and dangerous environmental pollutants that may cause fatal implications. Vitamin C is an important chain-breaking antioxidant and enzyme co-factor against heavy metals. The objective of the present study was to evaluate the toxicological effects of cadmium chloride, mercuric chloride, and their co-administration on biochemical parameters of blood serum and metal bioaccumulation in kidneys and also to elucidate the protective effect of vitamin C in rabbits against these metals. In the current research, cadmium chloride (1.5 mg/kg), mercuric chloride(1.2 mg/kg), and vitamin C (150 mg/kg of body weight) were orally administered to eight treatment groups of the rabbits (1, control; 2, vitamin; 3, CdCl2; 4, HgCl2; 5, vitamin + CdCl2; 6, vitamin + HgCl2; 7, CdCl2 + HgCl2, and 8, vitamin + CdCl2 + HgCl2). After the biometric measurements of all experimental rabbits, biochemical parameters viz. creatinine, cystatin C, uric acid, and alkaline phosphatase (ALP) and metal bioaccumulation were determined using commercially available kits and atomic absorption spectrophotometer, respectively. The levels of creatinine (28.3 ± 1.1 μmol/l), cystatin C (1932.5 ± 38.5 ηg/ml), uric acid (4.8 ± 0.1 mg/day), and ALP (51.6 ± 1.1 IU/l) were significantly (P < 0.05) increased due to administration of mercuric chloride but in the presence of vitamin C, the effects of mercuric chloride on creatinine (21.9 ± 1.4 μmol/l), cystatin C (1676.2 ± 42.2 ηg/ml), uric acid (3.9 ± 0.1 mg/day), and ALP (43.3 ± 0.8 IU/l) were less as compared to metal-exposed specimens. Similar results were found in rabbits treated with cadmium chloride and vitamin C and also with co-administration of both metals and vitamin C. Because of the bio-accumulative nature of cadmium chloride and mercuric chloride, these metals were accumulated in kidneys of rabbits, which might lead to deleterious effects. The results of the present study provide an insight into the toxicity of the cadmium chloride, mercuric chloride, and/or their combination on biochemical parameters as well as kidneys of the rabbits and the ameliorating potential of vitamin C against these metals is also evaluated.

Renal toxicity of heavy metals (cadmium and mercury) and their amelioration with ascorbic acid in rabbits

Background: Acute kidney injury (AKI) is highly prevalent in hospital inpatient populations, leading to significant mortality and morbidity, reduced quality of life and high short- and long-term health-care costs for the NHS. New diagnostic tests may offer an earlier diagnosis or improved care, but evidence of benefit to patients and of value to the NHS is required before national adoption.



Objectives: To evaluate the potential for AKI in vitro diagnostic tests to enhance the NHS care of patients admitted to the intensive care unit (ICU) and identify an efficient supporting research strategy.



Data sources: We searched ClinicalTrials.gov, The Cochrane Library databases, Embase, Health Management Information Consortium, International Clinical Trials Registry Platform, MEDLINE, metaRegister of Current Controlled Trials, PubMed and Web of Science databases from their inception dates until September 2014 (review 1), November 2015 (review 2) and July 2015 (economic model). Details of databases used for each review and coverage dates are listed in the main report.



Review methods: The AKI-Diagnostics project included horizon scanning, systematic reviewing, meta-analysis of sensitivity and specificity, appraisal of analytical validity, care pathway analysis, model-based lifetime economic evaluation from a UK NHS perspective and value of information (VOI) analysis.



Results: The horizon-scanning search identified 152 potential tests and biomarkers. Three tests, Nephrocheck® (Astute Medical, Inc., San Diego, CA, USA), NGAL and cystatin C, were subjected to detailed review. The meta-analysis was limited by variable reporting standards, study quality and heterogeneity, but sensitivity was between 0.54 and 0.92 and specificity was between 0.49 and 0.95 depending on the test. A bespoke critical appraisal framework demonstrated that analytical validity was also poorly reported in many instances. In the economic model the incremental cost-effectiveness ratios ranged from £11,476 to £19,324 per quality-adjusted life-year (QALY), with a probability of cost-effectiveness between 48% and 54% when tests were compared with current standard care.



Limitations: The major limitation in the evidence on tests was the heterogeneity between studies in the definitions of AKI and the timing of testing.



Conclusions: Diagnostic tests for AKI in the ICU offer the potential to improve patient care and add value to the NHS, but cost-effectiveness remains highly uncertain. Further research should focus on the mechanisms by which a new test might change current care processes in the ICU and the subsequent cost and QALY implications. The VOI analysis suggested that further observational research to better define the prevalence of AKI developing in the ICU would be worthwhile. A formal randomised controlled trial of biomarker use linked to a standardised AKI care pathway is necessary to provide definitive evidence on whether or not adoption of tests by the NHS would be of value.



Study registration: The systematic review within this study is registered as PROSPERO CRD42014013919.



Funding: The National Institute for Health Research Health Technology Assessment programme.

/pdf/the-future-for-diagnostic-tests-of-acute-kidney-injury-in-z0nd56wmma.pdf

The future for diagnostic tests of acute kidney injury in critical care: evidence synthesis, care pathway analysis and research prioritisation

In patients with acute kidney injury (AKI), serum creatinine level does not increase until moderate to severe reduction in glomerular filtration rate (GFR) occurs. Thus its use for estimating GFR in early AKI delays detection of kidney damage and making important therapeutic decisions. Moreover, serum cystatin C is not affected by gender, age, race, and muscle mass and also does not suffer from lag period for its rise in early AKI. We studied 200 healthy subjects and 130 AKI patients over a period of 2 years at a tertiary care hospital. Serum creatinine and serum cystatin C were studied and analyzed in relevance to early AKI. We found that 56.2% of patients of AKI group had normal levels of serum creatinine in early phase, while all patients had elevated serum cystatin C at same time. Multiple logistic regression analysis revealed cystatin C-based GFR reflecting decline in GFR with worsening AKI in better than creatinine-based GFR. Serum cystatin C is a better marker of renal function in early stages of AKI and is less affected by age, gender, muscle mass, and ethnicity. Its use helps in early therapeutic intervention and possibly favorable outcome.

VB Pandey

Papers

Serum cystatin C as a marker of renal function in detection of early acute kidney injury