Oxidative stress:New insights on the association of nonalcoholic fatty liver disease and atherosclerosis

Non-alcoholic fatty liver disease(NAFLD) represents the most common and emerging chronic liver disease worldwide. It includes a wide spectrum of liver diseasesranging from simple fatty liver to non-alcoholic steatohepatitis(NASH),which may progress to fibrosis and more severe liver complications such as cirrhosis,hepatocellular carcinoma and liver mortality. NAFLD is strongly associated with obesity,insulin resistance,hypertension,and dyslipidaemia,and is now regarded as the liver manifestation of the metabolic syndrome. The increased mortality of patients with NAFLD is primarily a result of cardiovascular disease and,to a lesser extent,to liver related diseases. Increased oxidative stress has been reported in both patients with NAFLD and patient with cardiovascular risk factors. Thus,oxidative stress represents a shared pathophysiological disorder between the two conditions. Several therapeutic strategies targeting oxidative stress reduction in patients with NAFLD have been proposed,with conflicting results. In particular,vitamin E supplementation has been suggested for the treatment of non-diabetic,non-cirrhotic adults with active NASH,although this recommendation is based only on the results of a single randomized controlled trial. Other antioxidant treatments suggested are resveratrol,silybin,L-carnitine and pentoxiphylline. No trial so far,has evaluated the cardiovascular effects of antioxidant treatment in patients with NAFLD. New,large-scale studies including as end-point also the assessment of the atherosclerosis markers are needed.

Reduced lysosomal acid lipase activity: A new marker of liver disease severity across the clinical continuum of non-alcoholic fatty liver disease?

Lysosomal acid lipase(LAL)plays a key role in intracellular lipid metabolism.Reduced LAL activity promotes increased multi-organ lysosomal cholesterol ester storage,as observed in two recessive autosomal genetic diseases,Wolman disease and Cholesterol ester storage disease.Severe liver steatosis and accelerated liver fibrosis are common features in patients with genetic LAL deficiency.By contrast,few reliable data are available on the modulation of LAL activity in vivo and on the epigenetic and metabolic factors capable of regulating its activity in subjects without homozygous mutations of the Lipase A gene.In the last few years,a less severe and non-genetic reduction of LAL activity was reported in children and adults with non-alcoholic fatty liver disease(NAFLD),suggesting a possible role of LAL reduction in the pathogenesis and progression of the disease.Patients with NAFLD show a significant,progressive reduction of LAL activity from simple steatosis to non-alcoholic steatohepatitis and cryptogenic cirrhosis.Among cirrhosis of different etiologies,those with cryptogenic cirrhosis show the most significant reductions of LAL activity.These findings suggest that the modulation of LAL activity may become a possible new therapeutic target for patients with more advanced forms of NAFLD.Moreover,the measurement of LAL activity may represent a possible new marker of disease severity in this clinical setting.

Treatment of a patient with congenital analbuminemia with atorvastatin and albumin infusion

Congenital analbuminemia is a rare autosomic recessive inherited disorder characterized by low plasma albumin and hypercholesterolemia, which may increase cardiovascular risk. Patients are essentially asymptomatic, apart from ease of fatigue, minimal ankle oedema and hypotension. There is no accepted strategy for safely treating both hypercholesterolemia and analbuminemia in order to eventually decrease the atherosclerotic risk. We report a case of congenital analbuminemia(1.0 g/dL) in a 38-year-old male with hypercholesterolemia(range: 406-475 mg/dL) and severe arterial dysfunction [no brachial artery flow-mediated dilation(FMD)]. Long-term, cholesterol-lowering treatment with atorvastatin was associated with the appearance of peripheral edema. Twomonths of infusion with albumin improved FMD(7%) and reduced serum cholesterol(273 mg/dL), supporting the hypothesis of a compensatory role of hypercholesterolemia. Statin treatment, together with periodical albumin infusions, may contribute to the safe reduction of cardiovascular risk.