Paradoxical reduction of plasma lipids and atherosclerosis in mice with adenine-induced chronic kidney disease and hypercholesterolemia.

Background: Atherosclerotic cardiovascular disease is prevalent among patients with chronic kidney disease (CKD). In this study, we initially aimed to test whether vascular calcification associated with CKD can worsen atherosclerosis. However, a paradoxical finding emerged from attempting to test this hypothesis in a mouse model of adenine-induced CKD. Methods: We combined adenine-induced CKD and diet-induced atherosclerosis in mice with a mutation in the low-density lipoprotein receptor gene. In the first study, mice were co-treated with 0.2% adenine in a western diet for 8 weeks to induce CKD and atherosclerosis simultaneously. In the second study, mice were pre-treated with adenine in a regular diet for 8 weeks, followed by a western diet for another 8 weeks. Results: Co-treatment with adenine and a western diet resulted in a reduction of plasma triglycerides and cholesterol, liver lipid contents, and atherosclerosis in co-treated mice when compared with the western-only group, despite a fully penetrant CKD phenotype developed in response to adenine. In the two-step model, renal tubulointerstitial damage and polyuria persisted after the discontinuation of adenine in the adenine-pre-treated mice. The mice, however, had similar plasma triglycerides, cholesterol, liver lipid contents, and aortic root atherosclerosis after being fed a western diet, irrespective of adenine pre-treatment. Unexpectedly, adenine pre-treated mice consumed twice the calories from the diet as those not pre-treated without showing an increase in body weight. Conclusion: The adenine-induced CKD model does not recapitulate accelerated atherosclerosis, limiting its use in pre-clinical studies. The results indicate that excessive adenine intake impacts lipid metabolism.

Rationale and design of the Hepatocellular carcinoma Early Detection Strategy study: A multi-center longitudinal initiative of the National Cancer Institute's Early Detection Research Network.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignancy with a steadily rising incidence and associated morbidity and mortality. Cirrhosis of the liver is presently the leading risk factor for developing HCC. Abdominal imaging, with or without alpha-fetoprotein (AFP) testing, every 6 months is the current surveillance strategy for patients at risk. The available biomarkers for detecting this cancer at an early stage have inadequate sensitivity and specificity. METHODS: The Hepatocellular carcinoma Early Detection Strategy (HEDS) study, a multi-center initiative of the National Cancer Institutes' (NCI) Early Detection Research Network (EDRN), launched an effort to establish what has become the nation's largest comprehensive biorepository and database on patients at high risk of developing HCC. The cohort has been developed in seven clinical centers across the USA. Subjects are enrolled for a five-year period involving data and specimen collection every six months in accordance with standard surveillance for HCC. Extensive clinical data are collected and specimens are stored at a central repository. RESULTS: The database and biorepository contain longitudinally collected clinical data and serum and plasma samples from 1482 participants with cirrhosis and without evidence of HCC at baseline. Fifty-six percent are male, 85% Caucasian, 30% have a history of chronic HCV and 71% have compensated cirrhosis. CONCLUSIONS: The HEDS cohort provides opportunities for the continued study of the incidence and course of HCC in a comprehensively followed population of patients at high risk for this malignancy. Further, the EDRN biorepository provides a distinct opportunity for the development of novel biomarkers. Trial registry URL: https://edrn.nci.nih.gov/protocols/316-hepatocellular-carcinoma-early-detection-strategy.

The Efficacy of Low-intensity Vibration to Improve Bone Health in Patients with End-stage Renal Disease Is Highly Dependent on Compliance and Muscle Response.

RATIONAL AND OBJECTIVES: Low intensity vibration (LIV) may represent a nondrug strategy to mitigate bone deficits in patients with end-stage renal disease. MATERIALS AND METHODS: Thirty end-stage renal patients on maintenance hemodialysis were randomized to stand for 20 minutes each day on either an active or placebo LIV device. Analysis at baseline and completion of 6-month intervention included magnetic resonance imaging (tibia and fibula stiffness; trabecular thickness, number, separation, bone volume fraction, plate-to-rod ratio; and cortical bone porosity), dual-energy X-ray absorptiometry (hip and spine bone mineral density [BMD]), and peripheral quantitative computed tomography (tibia trabecular and cortical BMD; calf muscle cross-sectional area). RESULTS: Intention-to-treat analysis did not show any significant changes in outcomes associated with LIV. Subjects using the active device and with greater than the median adherence (70%) demonstrated an increase in distal tibia stiffness (5.3%), trabecular number (1.7%), BMD (2.3%), and plate-to-rod ratio (6.5%), and a decrease in trabecular separation (-1.8%). Changes in calf muscle cross-sectional area were associated with changes in distal tibia stiffness (R = 0.85), trabecular bone volume/total volume (R = 0.91), number (R = 0.92), and separation (R = -0.94) in the active group but not in the placebo group. Baseline parathyroid hormone levels were positively associated with increased cortical bone porosity over the 6-month study period in the placebo group (R = 0.55) but not in the active group (R = 0.01). No changes were observed in the nondistal tibia locations for either group except a decrease in hip BMD in the placebo group (-1.7%). CONCLUSION: Outcomes and adherence thresholds identified from this pilot study could guide future longitudinal studies involving vibration therapy.