Therapeutic strategies for liver diseases based on redox control systems.

In the liver, reactive oxygen species (ROS) are constantly released during cellular metabolic processes, and excess ROS production can cause redox stress. The redox stress is both beneficial for and harmful to the survival of cells since it modulates the cellular redox control system. The redox control system is a series of cellular responses that are responsible for maintaining a balanced oxidation-reduction status. Many cellular processes including growth, proliferation, and senescence are sensitively regulated by the redox control system. Imbalance of redox induces redox stress and damages DNA, proteins, and lipids in cells, and further contributes to the pathogenesis of severe diseases and disorders like cancer. However, the cellular redox control system also utilizes redox stress-responsive pathways and increases antioxidant enzymes to aid cell survival. Therefore, a deeper understanding of the connection between the redox control system and liver disease is likely to pave the way for the future development of new therapeutic strategies. This review will examine the redox control systems in liver with responsive regulating molecules, current knowledge of the redox control system and liver disease, and suggest potential therapeutic targets for liver diseases.

Structural and functional characterization of recombinant human growth hormone isolated from transgenic pig milk.

This study aimed to establish and reproduce transgenic pigs expressing human growth hormone (hGH) in their milk. We also aimed to purify hGH from the milk, to characterize the purified protein, and to assess the potential of our model for mass production of therapeutic proteins using transgenic techniques. Using ~15.5 L transgenic pig milk, we obtained proteins with ≥ 99% purity after three pre-treatments and five column chromatography steps. To confirm the biosimilarity of our milk-derived purified recombinant hGH (CGH942) with commercially available somatropin (Genotropin), we performed spectroscopy, structural, and biological analyses. We observed no difference between the purified protein and Genotropin samples. Furthermore, rat models were used to assess growth promotion potential. Our results indicate that CGH942 promotes growth, by increasing bone development and body weight. Toxicity assessments revealed no abnormal findings after 4 weeks of continuous administration and 2 weeks of recovery. The no-observed-adverse-effect level for both males and females was determined to be 0.6 mg/kg/day. Thus, no toxicological differences were observed between commercially available somatropin and CGH942 obtained from transgenic pig milk. In conclusion, we describe a transgenic technique using pigs, providing a new platform to produce human therapeutic proteins.