Senescence in chronic liver disease: Is the future in aging?

Cellular senescence is a fundamental, complex mechanism with an important protective role present from embryogenesis to late life across all species. It limits the proliferative potential of damaged cells thus protecting against malignant change, but at the expense of substantial alterations to the microenvironment and tissue homeostasis, driving inflammation, fibrosis and paradoxically, malignant disease if the process is sustained. Cellular senescence has attracted considerable recent interest with recognition of pathways linking aging, malignancy and insulin resistance and the current focus on therapeutic interventions to extend health-span. There are major implications for hepatology in the field of fibrosis and cancer, where cellular senescence of hepatocytes, cholangiocytes, stellate cells and immune cells has been implicated in chronic liver disease progression. This review focuses on cellular senescence in chronic liver disease and explores therapeutic opportunities

Hepatorenal syndrome: aetiology, diagnosis, and treatment.

Acute renal impairment is common in patients with chronic liver disease, occurring in approximately 19% of hospitalised patients with cirrhosis. A variety of types of renal impairment are recognised. The most important of these is the hepatorenal syndrome, a functional renal impairment due to circulatory and neurohormonal abnormalities that underpin cirrhosis. It is one of the most severe complications of cirrhosis with survival often measured in weeks to months. A variety of treatment options exist with early diagnosis and appropriate treatment providing the best hope for cure. This paper provides a comprehensive and up-to-date review of hepatorenal syndrome and lays out the topic according to the following sections: pathophysiology, historical developments, diagnostic criteria and limitations, epidemiology, precipitating factors, predictors, clinical and laboratory findings, prognosis, treatment options, prophylaxis, and conclusion.Peer Reviewe

Axon diameter mapping in the presence of orientation dispersion using diffusion MRI

Axon diameter mapping using diffusion MRI provides more specific biomarkers than DTI indices. Earlier works assume a model of strictly parallel axons. However, such approximation is inadequate for most white matter regions in which axons fan or bend, resulting in significant orientation dispersion. Such dispersion, if unaccounted for, leads to overestimation of axon diameters. We ameliorates this problem by proposing a model that captures orientation dispersion explicitly. We demonstrate that recovery of axon diameters is possible even in the presence of orientation dispersion, supporting accurate axon diameter mapping in a much wider set of white matter than previously possibl

Salt and Water Retention Is Associated with Microinflammation and Endothelial Injury in Chronic Kidney Disease

BACKGROUND: Progressive chronic kidney disease (CKD) inevitably leads to salt and water retention and disturbances in the macro-and microcirculation. OBJECTIVES: We hypothesize that salt and water dysregulation in advanced CKD may be linked to inflammation and microvascular injury pathways. METHODS: We studied 23 CKD stage 5 patients and 11 healthy controls (HC). Tissue sodium concentration was assessed using 23Sodium magnetic resonance (MR) imaging. Hydration status was evaluated using bioimpedance spectroscopy. A panel of inflammatory and endothelial biomarkers was also measured. RESULTS: CKD patients had fluid overload (FO) when compared to HC (overhydration index: CKD = 0.5 ± 1.9 L vs. HC = -0.5 ± 1.0 L; p = 0.03). MR-derived tissue sodium concentrations were predominantly higher in the subcutaneous (SC) compartment (median [interquartile range] CKD = 22.4 mmol/L [19.4-31.3] vs. HC = 18.4 mmol/L [16.6-21.3]; p = 0.03), but not the muscle (CKD = 24.9 ± 5.5 mmol/L vs. HC = 22.8 ± 2.5 mmol/L; p = 0.26). Tissue sodium in both compartments correlated to FO (muscle: r = 0.63, p < 0.01; SC: rs = 0.63, p < 0.01). CKD subjects had elevated levels of vascular cell adhesion molecule (p < 0.05), tumor necrosis factor-alpha (p < 0.01), and interleukin (IL)-6 (p = 0.01) and lower levels of vascular endothelial growth factor-C (p = 0.04). FO in CKD was linked to higher IL-8 (r = 0.51, p < 0.05) and inversely associated to E-selectin (r = -0.52, p = 0.01). Higher SC sodium was linked to higher intracellular adhesion molecule (ICAM; rs = 0.54, p = 0.02). CONCLUSION: Salt and water accumulation in CKD appears to be linked with inflammation and endothelial activation pathways. Specifically IL-8, E-Selectin (in FO), and ICAM (in salt accumulation) may be implicated in the pathophysiology of FO and merit further investigation