Redox state constitutes an important background of numerous liver disorders. The redox state participates in the course of inflammatory, metabolic and proliferative liver diseases. Reactive oxygen species (ROS) are primarily produced in the mitochondria and in the endoplasmic reticulum of hepatocytes via the cytochrome P450 enzymes. Under the proper conditions, cells are equipped with special molecular strategies that control the level of oxidative stress and maintain a balance between oxidant and antioxidant particles. Oxidative stress represents an imbalance between oxidant and antioxidant agents. Hepatocytic proteins, lipids and DNA are among the cellular structures that are primarily affected by ROS and reactive nitrogen species. The process results in structural and functional abnormalities in the liver. Thus, the phenomenon of oxidative stress should be investigated for several reasons. First, it may explain the pathogenesis of various liver disorders. Moreover, monitoring oxidative markers among hepatocytes offers the potential to diagnose the degree of liver damage and ultimately to observe the response to pharmacological therapies. The present report focuses on the role of oxidative stress in selected liver diseases.

Autoimmune thyroid disease (AITD) is the most common organic specific illness of the thyroid gland. It may manifest as the overproduction or the decline of thyroxine and triiodothyronine. Hyperthyroidism develops due to the overproduction of hormones as an answer to the presence of stimulatory antibodies against the TSH receptor. Hashimoto’s thyroiditis (HT) is generally characterized by the presence of thyroid peroxidase and thyroglobulin antibodies, with a concomitant infiltration of lymphocytes in the thyroid. Due to the progressive destruction of cells, AITD can lead to subclinical or overt hypothyroidism. Pathophysiology of AITD is extremely complicated and still not fully understood, with genetic, environmental and epigenetic factors involved in its development. Due to increasing incidence and social awareness of this pathology, there is an urgent need to expand the background concerning AITD. A growing body of evidence suggests possible ways of treatment apart from traditional approaches. Simultaneously, the role of potential new biomarkers in the diagnosis and monitoring of AITD has been highlighted recently, too. Therefore, we decided to review therapeutic trends in the course of AITD based on its pathophysiological mechanisms, mainly focusing on HT. Another aim was to summarize the state of knowledge regarding the role of new biomarkers in this condition.

Hepatic encephalopathy is a medical phenomenon that is described as a neuropsychiatric manifestation of chronic or acute liver disease that is characterized by psychomotor, intellectual and cognitive abnormalities with emotional/affective and behavioral disturbances. This article focuses on the underlying mechanisms of the condition and the differences between hepatic encephalopathy and noncirrhotic hyperammonemic encephalopathy. Hepatic encephalopathy is a serious condition that can cause neurological death with brain edema and intracranial hypertension. It is assumed that approximately 60%-80% of patients with liver cirrhosis develop hepatic encephalopathy. This review explores the complex mechanisms that lead to hepatic encephalopathy. However, noncirrhotic hyperammonemic encephalopathy is not associated with hepatic diseases and has a completely different etiology. Noncirrhotic hyperammonemic encephalopathy is a severe occurrence that is connected with multiple pathogeneses.

Oxidative stress is known to be an inseparable factor involved in the presentation of liver disorders. Free radicals interfere with DNA, proteins, and lipids, which are crucial in liver metabolism, changing their expression and biological functions. Additionally, oxidative stress modifies the function of micro-RNAs, impairing the metabolism of hepatocytes. Free radicals have also been proven to influence the function of certain transcriptional factors and to alter the cell cycle. The pathological appearance of alcohol-related liver disease (ALD) constitutes an ideal example of harmful effects due to the redox state. Finally, ethanol-induced toxicity and overproduction of free radicals provoke irreversible changes within liver parenchyma. Understanding the underlying mechanisms associated with the redox state in the course of ALD creates new possibilities of treatment for patients. The future of hepatology may become directly dependent on the effective action against reactive oxygen species. This review summarizes current data on the redox state in the natural history of ALD, highlighting the newest reports on this topic.

Platelet (PLT) indices have been proposed as potential markers in the assessment of liver fibrosis and exacerbation of liver failure. The aim of our study was to verify mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) in alcohol‐related liver cirrhosis (ALC) and nonalcoholic fatty liver disease (NAFLD) patients. One hundred forty‐two patients with ALC, 92 with NAFLD, and 68 in control group were enrolled in this study. Hematological indices (MPV, PCT, and PDW) and serological (indirect and direct) markers of liver fibrosis (AAR, APRI, FIB‐4, GPR, PICP, PIIINP, TGF‐α, PDGF‐AB, laminin) were measured in each participant. MELD score in ALC patients and NAFLD fibrosis score (NFS) together with BARD score in the NAFLD group were also obtained. Results were compared between research and control groups. Then, a correlation between evaluated indices was performed in study groups. Receiver operating characteristic curves (ROCs) and area under the curve (AUC) values were applied to assess the diagnostic accuracy of measured indices. Significant increase in PDW and decrease in PCT in comparison to controls were noted in examined ALC (60.4% vs. 51.2% and 0.1% vs. 0.21%, respectively, p < 0.0001) and NAFLD (54.75% vs. 51.2% and 0.19 vs. 0.21%, respectively, p < 0.01) patients. Decreased level of MPV was observed in NAFLD group (7.85 fl vs. 8.90 fl, p < 0.0001). Additionally, PCT correlated with NFS (p < 0.0001). Evaluated PLT indices correlated with MELD score (MPV and PDW, p < 0.001; PCT, p < 0.05). They correlated with indirect and direct markers of liver fibrosis in the whole research group, too. PCT was the parameter with the greatest diagnostic accuracy in ALC patients (AUC = 0,839 for cutoff < 0.17%); in NAFLD group, it was MPV (AUC = 0,808 for cutoff < 7.9 fl). PCT in ALC and MPV in NAFLD can be perceived as potential diagnostic markers.

It is assumed that approximately 24–66% of patients with liver cirrhosis develop malnutrition. Numerous pathological processes lead to serious disorders of nutritional status in this group of patients. Malnutrition in the course of liver cirrhosis is associated with increased morbidity, complications, and low quality of life. Under these conditions, detection of malnutrition is of crucial importance. This review explores the complex mechanisms that lead to malnutrition in the course of liver cirrhosis and focuses on methods used in the assessment of nutritional status in cirrhotic patients. Among others, the role of bioelectrical impedance is highlighted. This noninvasive tool is promising and quite an accurate method of estimating body composition.