The liver fulfills central roles in metabolic control and detoxification and, as such, is continuously exposed to a plethora of insults. Importantly, the liver has a unique ability to regenerate and can completely recoup from most acute, non-iterative insults. However, multiple conditions, including viral hepatitis, non-alcoholic fatty liver disease (NAFLD), long-term alcohol abuse and chronic use of certain medications, can cause persistent injury in which the regenerative capacity eventually becomes dysfunctional, resulting in hepatic scaring and cirrhosis. Calcium is a versatile secondary messenger that regulates multiple hepatic functions, including lipid and carbohydrate metabolism, as well as bile secretion and choleresis. Accordingly, dysregulation of calcium signaling is a hallmark of both acute and chronic liver diseases. In addition, recent research implicates calcium transients as essential components of liver regeneration. In this review, we provide a comprehensive overview of the role of calcium signaling in liver health and disease and discuss the importance of calcium in the orchestration of the ensuing regenerative response. Furthermore, we highlight similarities and differences in spatiotemporal calcium regulation between liver insults of different etiologies. Finally, we discuss intracellular calcium control as an emerging therapeutic target for liver injury and summarize recent clinical findings of calcium modulation for the treatment of ischemic-reperfusion injury, cholestasis and NAFLD.

Alcohol consumption accounts for 3.8% of annual global mortality worldwide, and the majority of these deaths are due to alcoholic liver disease (ALD), mainly alcoholic cirrhosis. ALD is one of the most common indications for liver transplantation (LT). However, it remains a complicated topic on both medical and ethical grounds, as it is seen by many as a "self-inflicted disease". One of the strongest ethical arguments against LT for ALD is the probability of relapse. However, ALD remains a common indication for LT worldwide. For a patient to be placed on an LT waiting list, 6 mo of abstinence must have been achieved for most LT centers. However, this "6-mo rule" is an arbitrary threshold and has never been shown to affect survival, sobriety, or other outcomes. Recent studies have shown similar survival rates among individuals who undergo LT for ALD and those who undergo LT for other chronic causes of end-stage liver disease. There are specific factors that should be addressed when evaluating LT patients with ALD because these patients commonly have a high prevalence of multisystem alcohol-related changes. Risk factors for relapse include the presence of anxiety or depressive disorders, short pre-LT duration of sobriety, and lack of social support. Identification of risk factors and strengthening of the social support system may decrease relapse among these patients. Family counseling for LT candidates is highly encouraged to prevent alcohol consumption relapse. Relapse has been associated with unique histopathological changes, graft damage, graft loss, and even decreased survival in some studies. Research has demonstrated the importance of a multidisciplinary evaluation of LT candidates. Complete abstinence should be attempted to overcome addiction issues and to allow spontaneous liver recovery. Abstinence is the cornerstone of ALD therapy. Psychotherapies, including 12-step facilitation therapy, cognitive-behavioral therapy, and motivational enhancement therapy, help support abstinence. Nutritional therapy helps to reverse muscle wasting, weight loss, vitamin deficiencies, and trace element deficiencies associated with ALD. For muscular recovery, supervised physical activity has been shown to lead to a gain in muscle mass and improvement of functional activity. Early LT for acute alcoholic hepatitis has been the subject of recent clinical studies, with encouraging results in highly selected patients. The survival rates after LT for ALD are comparable to those of patients who underwent LT for other indications. Patients that undergo LT for ALD and survive over 5 years have a higher risk of cardiorespiratory disease, cerebrovascular events, and de novo malignancy.

Iron is an essential for organisms and the liver plays a major role in its storage. In pathologic conditions, where iron absorption from the intestine or iron uptake into the hepatocytes is increased, excess iron accumulates in the hepatocytes, leading to hepatocyte injury through the production of free radicals. Iron exerts its toxicity by catalyzing the generation of reactive oxygen species (ROS). ROS causes cell injury by inducing damage to the lysosomal, cytoplasmic, nuclear and mitochondrial membranes, apoptosis through activation of the caspase cascade, and hyperoxidation of fatty chains. In this manuscript, we reviewed the articles regarding role of iron in hepatic inflammation and hepatocellular carcinoma.

Hepatic fibrosis is characterized by the formation and deposition of excess fibrous connective tissue, leading to progressive architectural tissue remodeling. Irrespective of the underlying noxious trigger, tissue damage induces an inflammatory response involving the local vascular system and the immune system and a systemic mobilization of endocrine and neurological mediators, ultimately leading to the activation of matrix-producing cell populations. Genetic disorders, chronic viral infection, alcohol abuse, autoimmune attacks, metabolic disorders, cholestasis, alterations in bile acid composition or concentration, venous obstruction, and parasite infections are well-established factors that predispose one to hepatic fibrosis. In addition, excess fat and other lipotoxic mediators provoking endoplasmic reticulum stress, alteration of mitochondrial function, oxidative stress, and modifications in the microbiota are associated with non-alcoholic fatty liver disease and, subsequently, the initiation and progression of hepatic fibrosis. Multidisciplinary panels of experts have developed practice guidelines, including recommendations of preferred therapeutic approaches to a specific cause of hepatic disease, stage of fibrosis, or occurring co-morbidities associated with ongoing loss of hepatic function. Here, we summarize the factors leading to liver fibrosis and the current concepts in anti-fibrotic therapies.

Immunologically mediated liver diseases belong to the common extraintestinal manifestations of celiac disease. We have reviewed the current literature that addresses the association between celiac disease and liver disorders. We searched relevant articles on MEDLINE/PubMed up to 15 June 2018. The objective of the article is to provide a comprehensive and up-to-date review on the latest hypotheses explaining the pathogenetic relationship between celiac disease and liver injury. Besides the involvement of gut⁻liver axis, tissue transglutaminase antibodies, and impairment of intestinal barrier, we integrate the latest achievements made in elucidation of the role of gut microbiota in celiac disease and liver disorders, that has not yet been sufficiently discussed in the literature in this context. The further objective is to provide a complete clinical overview on the types of liver diseases frequently found in celiac disease. In conclusion, the review highlights the clinical implication, recommend a rational approach for managing elevated transaminases in celiac patients, and underscore the importance of screening for celiac disease in patients with associated liver disease.