Growth Hormone Mediates Its Protective Effect in Hepatic Apoptosis through Hnf6

Growth Hormone Signaling in Liver Diseases: Therapeutic Potentials and Controversies

Growth hormone (GH) and downstream insulin-like growth factor 1 (IGF1) signaling mediate growth and metabolism. GH deficiency causes short stature or dwarfism, and excess GH causes acromegaly. Although the association of GH/IGF1 signaling with liver diseases has been suggested previously, current studies are controversial and the functional roles of GH/IGF1 signaling are still undefined. GH supplementation therapy showed promising therapeutic effects in some patients, such as non-alcoholic fatty liver disease, but inhibition of GH signaling may be beneficial for other liver diseases, such as hepatocellular carcinoma. The functional roles of GH/IGF1 signaling and the effects of agonists/antagonists targeting this signaling may differ depending on the liver injury or animal models. This review summarizes current controversial studies of GH/IGF1 signaling in liver diseases and discusses therapeutic potentials of GH therapy.

Harnessing conserved signaling and metabolic pathways to enhance the maturation of functional engineered tissues

The development of induced-pluripotent stem cell (iPSC)-derived cell types offers promise for basic science, drug testing, disease modeling, personalized medicine, and translatable cell therapies across many tissue types. However, in practice many iPSC-derived cells have presented as immature in physiological function, and despite efforts to recapitulate adult maturity, most have yet to meet the necessary benchmarks for the intended tissues. Here, we summarize the available state of knowledge surrounding the physiological mechanisms underlying cell maturation in several key tissues. Common signaling consolidators, as well as potential synergies between critical signaling pathways are explored. Finally, current practices in physiologically relevant tissue engineering and experimental design are critically examined, with the goal of integrating greater decision paradigms and frameworks towards achieving efficient maturation strategies, which in turn may produce higher-valued iPSC-derived tissues.

Vitexin ameliorates glycochenodeoxycholate-induced hepatocyte injury through SIRT6 and JAK2/STAT3 pathways

Objectives

Vitexin, a natural flavonoid, is commonly found in many foods and traditional herbal medicines and has clear health benefits. However, the role of vitexin in cholestasis is presently unclear. This study investigated whether vitexin mitigated glycochenodeoxycholate (GCDC)-induced hepatocyte injury and further elucidated the underlying mechanisms.

Materials and Methods

A cell counting kit-8 (CCK-8) assay was conducted to evaluate cell viability. The mitochondrial membrane potential (MMP, Δψm), reactive oxygen species (ROS) levels, and apoptosis rate of hepatocytes exposed to GCDC were detected by flow cytometry (FCM). We then measured the cytoprotective effects of vitexin against oxidative stress. The molecular signaling pathway was further investigated by using Western blotting and signaling pathway inhibitors.

Results

Here, we showed that vitexin increased cell viability and reduced cell apoptosis, necroptosis, and oxidative stress in a dose-dependent manner in GCDC-treated hepatocytes. In addition, by using selective inhibitors, we further confirmed that inhibition of the JAK2/STAT3 pathway by vitexin was mediated by prolonged activation of Sirtuin 6 (SIRT6).

Conclusion

Vitexin attenuated GCDC-induced hepatocyte injury via SIRT6 and the JAK2/STAT3 pathways.

Host Transcription Factors in Hepatitis B Virus RNA Synthesis

The hepatitis B virus (HBV) chronically infects over 250 million people worldwide and is one of the leading causes of liver cancer and hepatocellular carcinoma. HBV persistence is due in part to the highly stable HBV minichromosome or HBV covalently closed circular DNA (cccDNA) that resides in the nucleus. As HBV replication requires the help of host transcription factors to replicate, focusing on host protein–HBV genome interactions may reveal insights into new drug targets against cccDNA. The structural details on such complexes, however, remain poorly defined. In this review, the current literature regarding host transcription factors’ interactions with HBV cccDNA is discussed.

Outcomes after multiple courses of granulocyte colony-stimulating factor and growth hormone in decompensated cirrhosis: A randomized trial

Decompensated cirrhosis (DC) carries a high mortality. Liver transplantation (LT) is the treatment of choice; however, the limited availability of donor organs has resulted in high waitlist mortality. The present study investigated the impact of multiple courses of granulocyte-colony stimulating factor (G-CSF) with or without growth hormone (GH) in these patients. Sixty-five patients with DC were randomized to standard medical therapy (SMT) plus G-CSF 3 monthly plus GH daily (group A; n = 23) or SMT plus G-CSF (group B; n = 21) or SMT alone (group C; n = 21). The primary outcome was transplant-free survival (TFS) at 12 months. Secondary outcomes were mobilization of CD34⁺ cells at day 6 and improvement in clinical scores, liver stiffness, nutrition, episodes of infection, and quality of life (QOL) at 12 months. There was significantly better 12-month TFS in groups A and B than in group C (P = 0.001). At day 6 of therapy, CD34⁺ cells increased in groups A and B compared to baseline (P < 0.001). There was a significant decrease in clinical scores, improvement in nutrition, better control of ascites, reduction in liver stiffness, lesser infection episodes, and improvement in QOL scores in groups A and B at 12 months as compared to baseline (P < 0.05). The therapies were well tolerated.

CONCLUSION

Multiple courses of G-CSF improved 12-month TFS, mobilized hematopoietic stem cells, improved disease severity scores, nutrition, fibrosis, QOL scores, ascites control, reduced infections, and the need for LT in patients with DC. However, the use of GH was not found to have any additional benefit. (Hepatology 2017).