Investigation of genome instability in patients with non-alcoholic steatohepatitis

Cellular Senescence in Liver Disease and Regeneration

Cellular senescence is an irreversible cell cycle arrest implemented by the cell as a result of stressful insults. Characterized by phenotypic alterations, including secretome changes and genomic instability, senescence is capable of exerting both detrimental and beneficial processes. Accumulating evidence has shown that cellular senescence plays a relevant role in the occurrence and development of liver disease, as a mechanism to contain damage and promote regeneration, but also characterizing the onset and correlating with the extent of damage. The evidence of senescent mechanisms acting on the cell populations of the liver will be described including the role of markers to detect cellular senescence. Overall, this review intends to summarize the role of senescence in liver homeostasis, injury, disease, and regeneration.

Diet induces hepatocyte protection in fatty liver disease via modulation of PTEN signaling

Fatty liver disease (FLD) is characterized by accumulation of excess fat in the liver. The underlying molecular mechanism associated with the progression of the disease has been in elusive. Hepatocellular demise due to increased oxidative stress resulting in an inflammatory response may be a key feature in FLD. Recent advances in molecular biology have led to an improved understanding of the molecular pathogenesis, suggesting a critical association between the PI3K/AKT/PTEN signaling pathway and FLD. In particular, PTEN has been associated with regulating the pathogenesis of hepatocyte degeneration. Given the function of mitochondria in reactive oxygen species (ROS) generation and the initiation of oxidative stress, the mitochondrial antioxidant network is of interest. It is vital to balance the activity of intracellular key molecules to maintain a healthy liver. Consequently, onset of FLD may be delayed using dietary protective agents that alter PTEN signaling and reduce ROS levels. The advancement of research on dietary regulation with a focus on modulatory roles in ROS generation and PTEN associated signaling is summarized in the current study, supporting further preventive and therapeutic exploration.

The Role of Senescence in the Development of Nonalcoholic Fatty Liver Disease and Progression to Nonalcoholic Steatohepatitis

In recent years, cellular senescence has generated a lot of interest among researchers because of its involvement in both the normal aging process and common human diseases. During senescence, cells undergo alterations that include telomere shortening, nuclear area enlargement, and genomic and mitochondrial DNA damage, leading to irreversible cell cycle arrest, and secretion of proinflammatory cytokines. Evidence suggests that the complex process of senescence is involved in the development of a plethora of chronic diseases including metabolic and inflammatory disorders and tumorigenesis. Recently, several human and animal studies have emphasized the involvement of senescence in the pathogenesis and development of liver steatosis including the progression to nonalcoholic steatohepatitis (NASH) as characterized by the additional emergence of inflammation, hepatocyte ballooning, and liver fibrosis. The development of nonalcoholic fatty liver disease (NAFLD) and its progression to NASH are commonly accompanied by several pathophysiological events including metabolic dysregulation and inflammatory phenomena occurring within the liver that may contribute to or derive from cellular senescence, implying that the latter may be both a stimulus and a consequence of the disease. Conclusion: In this review, we summarize the current literature on the impact of cellular senescence in NAFLD/NASH and discuss the effectiveness and safety of novel senolytic drugs and therapeutic options available to delay or treat the disease. Finally, we identify the open questions and issues to be addressed in the near future.

Plasma fatty acid composition in French-Canadian children with non-alcoholic fatty liver disease: Effect of n-3 PUFA supplementation

Non-alcoholic fatty liver disease (NAFLD) represents one of the most common causes of liver disease worldwide. As the NAFLD pathogenesis is associated with diet and lifestyle, the aims of the present work are to assess fatty acid (FA) composition in NAFLD young French-Canadian, to determine whether treatment with n-3 FA improves the plasma FA profile, and to define the time on the effectiveness of n-3 FA supplementation. Baseline characteristics of the NAFLD subjects show increased, anthropometric and biochemical parameters. Their plasma FA composition is characterized by a percent increase in total n-6 FA and a high proportion of saturated and total monounsaturated FA, as well as a decrease in Δ5 and increase in Δ6 desaturases. In conclusion, our results document for the first time the composition of plasma FAs in NAFLD young French Canadian and the efficacy of 3-month supplementation to improve the proportion of n-3 FA in their plasma.