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The anti-tumoral activity of somatostatin has been demonstrated in both animal experiments and human tumors. Clinical trials have reported conflicting results. We therefore hypothesized that somatostatin might have different effects in various hepatocellular carcinoma cells. Their clarification would possibly allow for the better selection of patients suitable for the optimal treatment results. We studied the mRNA and protein expression of TNF receptors and the TNFa-induced apoptosis using the HepG2 and the Hep3B human hepatocellular carcinoma cells after incubation with the somatostatin analog octreotide. RT-PCR, Western blot, and parameters associated with apoptosis (NF-kB nuclear translocation, P65 Ser536 and P65 Ser468 phosphorylation, DNA fragmentation) were assessed. Only TNFR1 was constitutively present in the two cell lines. Octreotide incubation led to an earlier reduction in TNFR1 mRNA and protein in HepG2 compared to Hep3B cells (1 h and 6–12 h, respectively). NF-kB translocation to the nucleus was induced by TNFa and was more prominent in Hep3B. Translocation was unaffected by octreotide. Serine phosphorylation was significantly induced by TNFa and was more evident in the Hep3B cells. TNFa-induced Ser536 phosphorylation was inhibited by octreotide only in the HepG2 cells. DNA fragmentation was not influenced by either octreotide or TNFa in the HepG2 cells, but TNFa induced fragmentation in the Hep3B cells (1.8-fold increase) verified by the TUNEL index (43 compared to 19 for the HepG2 cells). Octreotide and TNFa co-incubation induced apoptosis in the HepG2 cells (1.7-fold increase compared to controls) but inhibited apoptosis in the Hep3B cells. We conclude that: (1) octreotide reduced TNFR1 receptor expression in both cell lines, (2) parameters of apoptosis were differentially affected by octreotide in the two cell lines, and (3) this might be a partial explanation for the conflicting results of somatostatin analog treatment in human hepatocellular carcinoma trials.

The pathogenesis of acute and chronic pancreatitis has recently evolved as new findings demonstrate a complex mechanism operating through various pathways. In this review, the current evidence indicating that several mechanisms act in concert to induce and perpetuate pancreatitis were presented. As autophagy is now considered a fundamental mechanism in the pathophysiology of both acute and chronic pancreatitis, the fundamentals of the autophagy pathway were discussed to allow for a better understanding of the pathophysiological mechanisms of pancreatitis. The various aspects of pathogenesis, including trypsinogen activation, ER stress and mitochondrial dysfunction, the implications of inflammation, and macrophage involvement in innate immunity, as well as the significance of pancreatic stellate cells in the development of fibrosis, were also analyzed. Recent findings on exosomes and the miRNA regulatory role were also presented. Finally, the role of autophagy in the protection and aggravation of pancreatitis and possible therapeutic implications were reviewed.

It is generally accepted that eradication of Helicobacter pylori (H. pylori) infection may reduce the risk of the development of gastric cancer. Recommendations for global generalized tests and treat all individuals detected positive for H. pylori infection are currently proposed. However, the bacterium is commensal and harmless for the vast majority of the infected population. Moreover, eradication may have detrimental consequences in several groups of patients. In the present review, the current epidemiological data and recommendations for eradication in connection with the possible beneficial effects of the colonization with H. pylori in diseases such as asthma and allergies or chronic gastro-intestinal disorders such as inflammatory bowel disease and Barrett’ esophagus are presented the problems with increasing antibiotic resistance were also examined. Specific groups of patients where eradication of H. pylori may be necessary and endoscopic surveillance is advised were identified. Finally, based on the paradox of high H. pylori prevalence and low gastric risk as reported for areas of Africa, Asia, South America, and Greece, alternatives that may replace the widespread eradication of H. pylori with equal if not better results and more prudent use of the available financial resources are proposed. Mediterranean diets and alcohol and smoking reduction are among the well documented alternatives.

The intestinal microbiota is closely related to liver diseases via the intestinal barrier and bile secretion to the gut. Impairment of the barrier can translocate microbes or their components to the liver where they can contribute to liver damage and fibrosis. The components of the barrier are discussed in this review along with the other elements of the so-called gut–liver axis. This bidirectional relation has been widely studied in alcoholic and non-alcoholic liver disease. However, the involvement of microbiota in the pathogenesis and treatment of viral liver diseases have not been extensively studied, and controversial data have been published. Therefore, we reviewed data regarding the integrity and function of the intestinal barrier and the changes of the intestinal microbioma that contribute to progression of Hepatitis B (HBV) and Hepatitis C (HCV) infection. Their consequences, such as cirrhosis and hepatic encephalopathy, were also discussed in connection with therapeutic interventions such as the effects of antiviral eradication and the use of probiotics that may influence the outcome of liver disease. Profound alterations of the microbioma with significant reduction in microbial diversity and changes in the abundance of both beneficial and pathogenic bacteria were found.

The pathogenesis of inflammatory bowel disease (IBD) implicates several interconnecting factors. Immunity and external factors interact, and most aspects are still under investigation. Autophagy and apoptosis are two critical pathways that decide the fate of the individual cells of the intestinal mucosa. Experimental and clinical data indicate that the two are closely interconnected and usually mutually exclusive. However, despite the abundant information on their role, very limited translation into therapeutic application has been seen during recent years. In this review, research on these two pathways is presented. After a general overview of autophagy and apoptosis, their association with IBD, including the important mitophagy and ferroptosis, is discussed. The influence of autophagy- and apoptosis-related genes is also discussed. Finally, the interplay of autophagy and apoptosis in IBD is presented and the implications for treatment applications are examined. It is shown that dysregulated autophagy leads to increased apoptosis of enterocytes and impairs the tight junction proteins of the protective intestinal barrier. Dysregulated autophagy also induces the downregulation of lysozyme and the other antimicrobial proteins’ production. Mucus production by the goblet cells is also reduced due to defective autophagy and increased apoptosis.

The pathogenesis of primary biliary cholangitis (PBC) is particularly complicated as both intrinsic and extrinsic factors are implicated. Several forms of cellular death, both programmable and non-programmable, operate leading biliary epithelial cells (BECs) to elimination. The precise role of critical pathways like autophagy, apoptosis, senescence, and their interplay has not been fully clarified. Therefore, in this review, data on these important mechanisms are presented and their implication in PBC is discussed. The interplay of the three mechanisms is examined and the factors that drive them are analyzed. Moreover, the upstream drivers of autophagy, apoptosis, and senescence are presented. They include the loss of the protective bicarbonate umbrella in BECs due to the reduction of activity of the anion exchanger 2 (AE2) with the resultant activation of the intracellular soluble adenylyl cyclase (sAC). The role of toxic bile acids is also presented. A sequence of events is proposed including involvement of the gut-liver axis and the possible role of ferroptosis. Finally, a brief account of the initial trigger of the disease is given.