Impact of sodium butyrate and mild hypothermia on metabolic and physiological behaviour of CHO TF 70R cells

Background: To reduce costs associated with productivity of recombinant proteins in the biopharmaceutical industry, research has been focused on regulatory principals of growth and survival during the production phases of the cell culture. The main strategies involve the regulation of cell proliferation by the modulation of cell cycle control points (G1/S or G2/M) with mild hypothermia and the addition of sodium butyrate (NaBu). In this study, batch culture strategies were evaluated using CHO TF 70R cells producing the recombinant human tissue plasminogen activator (rh-tPA), to observe their individual and combined effect on the cellular physiological state and relevant kinetic parameters. Results: NaBu addition has a negative effect on the mitochondrial membrane potential (ΔΨm), the values of which are remarkably diminished in cultures exposed to this cytotoxic compound. This effect was not reflected in a loss of cell viability. NaBu and mild hypothermic conditions increased the doubling time in the cell cultures, suggesting that these strategies triggered a general slowing of each cell cycle phase in a different way. Finally, the individual and combined effect of NaBu and mild hypothermia produced an increase in the specific rh-tPA productivity in comparison to the control at 37°C without NaBu. Nevertheless, both strategies did not have a synergistic effect on the specific productivity. Conclusions: The combination of NaBu addition and mild hypothermic condition causes an impact on physiological and metabolic state of CHO TF 70R cells, decreasing cell growth rate and improving glucose consumption efficiency. These results therefore provide a promising strategy to increase specific productivity of rh-tPA.

Mechanism of Moxibustion Regulation on Cellular Apoptosis in Rat's Precancerous Lesion of Primary Hepatocellular Carcinoma / 针灸推拿医学（英文版）

To investigate the mechanism of moxibustion in regulating cellular apoptosis in rat's precancerous lesion of primary hepatocellular carcinoma (HCC). Methods:Seventy-four rats were randomly allocated to normal group,model group and moxibustion group,and the diethylic nitrosamine (DEN) was used to establish HCC model. Moxibustion with moxa cone which is as big as a grain of wheat was performed on acupoint Zusanli (ST 36),3 cones for each acupoint and 0.5 mg for each cone,the treatment was given once a day,totally 16 weeks. Then the changes in the body weight,liver weight and thymus weight,a morphological change in the liver tissue and changes in γ-GT and GST were observed;Immunohistochemical staining method was adopted to observe the tendency of changes in relevant apoptosis genes such as C-myc,N-ras and mutant type P53,and the influence of moxibustion on cell cycle modulation genes such as cyclinD1,CDK4 and p16. Results:Moxibustion could reduce the activities of γ-GT and GST in the blood,obviously decrease the protein expression of relevant apoptosis genes such as C-myc,N-ras and mutant type P53 and markedly inhibit the over-expression of relevant cell cycle modulation genes such as cyclinD1 and CDK4 and the mutation of cell cycle modulation gene p16. Conclusion:Moxibustion might play a certain role in relieving HCC precancerous lesion and its action mechanism might be related to the regulation on partial apoptosis genes.