Effect of the ratios of unsaturated fatty acids on the expressions of genes related to fat and protein in the bovine mammary epithelial cells.

The objective of this study was to evaluate the effects of the different ratios of unsaturated fatty acids (UFAs) (oleic acid, linoleic acid, and linolenic acid) on the cell viability and triacylglycerol (TAG) content, as well as the mRNA expression of the genes related to lipid and protein synthesis in bovine mammary epithelial cells (BMECs). Primary cells were isolated from the mammary glands of Holstein dairy cows and were passaged twice. Afterward, the cells were randomly allocated to six treatments, five UFA-treated groups, and one control group. For all of the treatments, the the fetal bovine serum in the culture solution was replaced with fatty acid-free BSA (1 g/L), and the cells were treated with different ratios of oleic, linoleic, and linolenic acids (0.75:4:1, 1.5:10:1, 2:13.3:1, 3:20:1, and 4:26.7:1) for 48 h, which were group 1 to group 5. The control culture solution contained only fatty acid-free BSA without UFAs (0 µM). The results indicated that the cell viability was not affected by adding different ratios of UFAs, but the accumulation of TAG was significantly influenced by supplementing with different ratios of UFAs. Adding different ratios of UFAs suppressed the expression of ACACA and FASN but had the opposite effect on the abundances of FABP3 and CD36 mRNA. The expression levels of PPARG, SPEBF1, CSN1S1, and CSN3 mRNA in the BMECs were affected significantly after adding different ratios of UFAs. Our results suggested that groups 1, 2, and 3 (0.75:4:1, 1.5:10:1, and 2:13.3:1) had stronger auxo-action on fat synthesis in the BMECs, where group 3 (2:13.3:1) was the best, followed by group 4 (3:20:1). However, group 5 (4:26.7:1) was the worst. Genes related to protein synthesis in the BMECs were better promoted in groups 2 and 3, and group 3 had the strongest auxo-action, whereas the present study only partly examined the regulation of protein synthesis at the transcriptional level; more studies on translation level are needed in the future. Therefore, when combining fat and protein synthesis, group 3 could be obviously fat and protein synthesis in the BMECs concurrently. However, further studies are necessary to elucidate the mechanism for regulating fat and protein synthesis in the BMECs.

Stem cells and hepatic cirrhosis.

Hepatic cirrhosis is defined as the histological development of regenerative nodules surrounded by fibrous bands in response to chronic liver injury, which leads to portal hypertension and end-stage liver disease. The majority of patients with hepatic cirrhosis die from life-threatening complications at early age. Liver transplantation has been the most effective treatment for patients with hepatic cirrhosis. Since liver transplantation is critically limited by the shortage of available donor livers, searching for an effective alternative therapy has attracted great interest in preclinical studies. The encouraging advances in stem cell research have paved the way towards the treatment of the end-stage of chronic liver disease. In view of the pathogenic fundamentals of hepatic cirrhosis, stem cell-based treatment should be aimed to complement or replace damaged liver cells and to correct the imbalanced extracellular matrix regeneration/degradation. This review is intended to describe the characteristics and therapeutic potential of various liver repair-related stem cells, including hepatocytes, liver progenitor cells, hematopoietic stem cells, mesenchymal stem cells, embryonic stem cells and induced pluripotent stem cells. Since autologous adult stem cells have the least number of obstacles for clinical application, their potential interventions on cirrhosis are especially illustrated in terms of the cellular and molecular mechanisms of hepatic fibrogenesis.