24 research outputs found
Differential regulation of serum microRNA expression by HNF1β and HNF1α transcription factors.
We aimed to identify microRNAs (miRNAs) under transcriptional control of the HNF1β transcription factor, and investigate whether its effect manifests in serum.This article is freely available via Open Access. Click on the 'Additional Link' above to access the full-text via the publisher's site.Published (Open Access
Western diet causes obesity-induced nonalcoholic fatty liver disease development by differentially compromising the autophagic response.
Nonalcoholic fatty liver disease (NAFLD) is characterized by the development of steatosis, which can ultimately compromise liver function. Mitochondria are key players in obesity-induced metabolic disorders; however, the distinct role of hypercaloric diet constituents in hepatic cellular oxidative stress and metabolism is unknown. Male mice were fed either a high-fat (HF) diet, a high-sucrose (HS) diet or a combined HF plus HS (HFHS) diet for 16 weeks. This study shows that hypercaloric diets caused steatosis; however, the HFHS diet induced severe fibrotic phenotype. At the mitochondrial level, lipidomic analysis showed an increased cardiolipin content for all tested diets. Despite this, no alterations were found in the coupling efficiency of oxidative phosphorylation and neither in mitochondrial fatty acid oxidation (FAO). Consistent with unchanged mitochondrial function, no alterations in mitochondrial-induced reactive oxygen species (ROS) and antioxidant capacity were found. In contrast, the HF and HS diets caused lipid peroxidation and provoked altered antioxidant enzyme levels/activities in liver tissue. Our work provides evidence that hepatic oxidative damage may be caused by augmented levels of peroxisomes and consequently higher peroxisomal FAO-induced ROS in the early NAFLD stage. Hepatic damage is also associated with autophagic flux impairment, which was demonstrated to be diet-type dependent. The HS diet induced a reduction in autophagosomal formation, while the HF diet reduced levels of cathepsins. The accumulation of damaged organelles could instigate hepatocyte injuries and NAFLD progression
Case report: lipid inclusion in glomerular endothelial and mesangial cells in a patient after contrast medium injection
Abstract Background It is well-recognized that injection of iodinated radiographic contrast media (CM) sometimes causes acute renal injury via multiple mechanisms, such as vasoconstriction, toxicity on glomerular endothelium and tubular epithelium and so forth. Case presentation A 51-year-old man developed acute renal injury with proteinuria after CM administration. To our surprise, in his renal biopsy sample the myelin figure like structure was observed in glomerular endothelium and mesangial cells by transmission electron microscopy. However the patient didn’t has any clinic clues of Fabry disease and other lysosomal storage disorders. Moreover in vitro cultured glomerular endothelial and mesangial cells we found CM triggers lipid aggregation along with the increased CD36 and decreased ABCA1 abundance. Thus this patient was administrated statin to correct the aberrant lipid trafficking, 2 months later at his next visit we found his renal function partially recovered with reduced proteinuria. Conclusions Besides the well-known underlying mechanisms, CM may cause renal impairment by triggering the dysregulated transportation of lipid. Furthermore statin is suggested to be a very promising medicine to decrease side effects of CM
The Alterations of Mitochondrial Function during NAFLD Progression-An Independent Effect of Mitochondrial ROS Production
The progression of non-alcoholic fatty liver (NAFL) into non-alcoholic steatohepatitis implicates multiple mechanisms, chief of which is mitochondrial dysfunction. However, the sequence of events underlying mitochondrial failure are still poorly clarified. In this work, male C57BL/6J mice were fed with a high-fat plus high-sucrose diet for 16, 20, 22, and 24 weeks to induce NAFL. Up to the 20th week, an early mitochondrial remodeling with increased OXPHOS subunits levels and higher mitochondrial respiration occurred. Interestingly, a progressive loss of mitochondrial respiration along "Western diet" feeding was identified, accompanied by higher susceptibility to mitochondrial permeability transition pore opening. Importantly, our findings prove that mitochondrial alterations and subsequent impairment are independent of an excessive mitochondrial reactive oxygen species (ROS) generation, which was found to be progressively diminished along with disease progression. Instead, increased peroxisomal abundance and peroxisomal fatty acid oxidation-related pathway suggest that peroxisomes may contribute to hepatic ROS generation and oxidative damage, which may accelerate hepatic injury and disease progression. We show here for the first time the sequential events of mitochondrial alterations involved in non-alcoholic fatty liver disease (NAFLD) progression and demonstrate that mitochondrial ROS are not one of the first hits that cause NAFLD progression